H-bomb See: Nuclear weapon.
21st Century Webster's Family Encyclopedia - Haeckel, Ernst von to Health Insurance, National
Haeckel, Ernst von (1834–1919), German biologist best remembered for his vociferous support of Darwin's theory of evolution and for his own theory that ontogeny (the development of an individual organism) recapitulates phylogeny (its evolutionary stages), a theory now discredited.
Hafiz (Shams ad-din Mohammed; c.1325–c.90 B.C.), Persian lyric poet and courtier at Shiraz, considered one of the greatest medieval Islamic poets.
Hafnium, chemical element, symbol Hf; for physical constants see Periodic Table.
Hagar See: Ishmael.
Hagfish, any of a family (Myxinidae) of predatory marine fishes related to the lamprey.
Haggai, Book of, book of the Old Testament, 10th of the Old Testament Minor Prophets, dated 520–519 B.C.
Haggard, Sir Henry Rider (1856–1925), English author of romantic adventure novels with authentic African backgrounds.
Hagia Sophia, or Santa Sophia, massive cathedral raised in Constantinople (now Istanbul) by the Byzantine emperor Justinian I; completed in A.D. 537.
Hague, The (Dutch: Gravenhage or Den Haag; pop. 445,700), seat of government of the Netherlands, capital of South Holland province, and headquarters of the International Court of Justice.
Hague, Frank (1876–1956), U.S. politician, mayor of Jersey City, N.J., for 30 years, and controller of one of the United State's most powerful political machines.
Hague Peace Conferences, 2 conferences (1899, 1907) held at The Hague, the Netherlands, at Russia's request, to discuss belligerency rules and war conventions.
Hague Tribunal, or International Permanent Court of Arbitration, court established by the first Hague Peace Conference (1899).
Hahn, Otto (1879–1968), German chemist awarded the 1944 Nobel Prize for chemistry for his splitting of the uranium atom in 1939 and his discovery of the possibility of chain reactions.
Hahnemann, (Christian Friedrich) Samuel (1755–1843), German physician and founder of homeopathic medicine.
Haida, tribe of Native Americans of the Pacific northwest, living primarily on islands off the coast of British Columbia and Alaska.
Haifa (pop. 251,000), port city in northern Israel, an important manufacturing and transportation center.
Haig, Alexander Meigs, Jr. (1924– ), U.S. general and secretary of state (1981–82).
Haig, Douglas, 1st Earl (1861–1928), British commander in World War I, blamed for the misconduct of the Somme and Ypres campaigns (1916–17).
Haiku, traditional unrhymed Japanese poem of 3 lines of 5, 7, and 5 syllables.
Hail, ice pellets that sometimes fall during thunderstorms.
Haile Selassie (1891–1975), reigning name of Ras Tafari, emperor of Ethiopia (1930–74).
Haiphong (pop. 1,447,500), city in northeast Vietnam, on the Red River delta near the Gulf of Tonkin.
Hair, outgrowth of the skin in mammals, sometimes thickening to form wool or fur.
Hair snake See: Horsehair worm.
Hairdressing, care and arranging of hair, including cutting, setting, styling, tinting, bleaching, straightening, waving, and other procedures.
Hairworm See: Horsehair worm.
Haise, Fred Wallace, Jr. (1933– ), U.S. astronaut (1966–79), pilot of the lunar module of the Apollo 13 mission (1970), during which an explosion disabled the command module and prevented the lunar landing.
Haiti, Republic of, independent country occupying the western third of the island of Hispaniola in the Caribbean Sea. The Dominican Republic occupies the rest of the island. The capital is Port-au-Prince. Haiti is mountainous, dominated by two peninsulas extending westward into the Windward Passage, which separates Hispaniola from Cuba. Between the peninsulas is the Gulf of Gonaïves, with G…
Hajj, or Hadj, pilgrimage to the Muslim world's holiest city, Mecca, in what is now Saudi Arabia.
Hake, any of various fish of the family Merlucciidae, related to the cod but with a different arrangement of fins.
Hakluyt, Richard (1552?–1616), English geographer and promoter of exploration and colonization.
Halas, George Stanley (1895–1983), founder, owner, and coach of the Chicago Bears (originally called the Decatur Staleys), one of the founding teams of the National Football League (NFL).
Halcyon days, period of tranquility.
Haldimand, Sir Frederick (1718–91), Swiss-born British general and governor of Quebec (1778–86).
Hale, Edward Everett (1822–1909), U.S. author, editor, and Unitarian minister, best known for his short novel The Man Without a Country (1863).
Hale, George Ellery (1868–1938), U.S. astronomer who discovered the magnetic fields of sunspots and invented (c.1890) the spectroheliograph.
Hale, Nathan (1755–1776), American revolutionary who was caught in disguise behind British lines on Long Island and hanged as a spy on Sept. 22, 1776.
Hale Observatories See: Mount Wilson Observatory; Palomar Observatory.
Hale, Sarah Josepha (1788–1879), U.S. feminist journalist, editor of Ladies' Magazine (1828–37) and Godey's Lady's Book (from 1837).
Haleakala National Park, park on the island of Maui, in Hawaii, encompassing the dormant volcano Mt.
Halevi, Judah (1085?–1141?), Jewish rabbi, philosopher, and poet who lived and worked in Muslim Spain.
Haley, Alex Palmer (1921–92), U.S. author.
Half-life See: Radioactivity.
Halibut, any of various fish of the family Hippoglossidae.
Halifax (320,500), capital of Nova Scotia and eastern Canada's chief winter (ice free) port.
Halite See: Salt.
Hall effect, electrical effect produced when current flows through a magnetic field.
Hall of Fame (formerly The Hall of Fame for Great Americans), memorial to Americans who have achieved great fame in various fields.
Hall, Granville Stanley (1844–1924), U.S. psychologist and educator best known for founding the American Journal of Psychology (1887), the first U.S. psychological journal.
Hall, James N.
Hall, Lyman (1724–90), American Revolutionary leader.
Hall, Prince (1748–1807), founder of the African Lodge, the first all-black Masonic lodge in America (chartered by the English Masons 1787).
Halleck, Henry Wager (1815–72), U.S.
Haller, Albrecht von (1708–77), Swiss biologist.
Halley, Edmund (1656–1742), English astronomer.
Halley's Comet, first periodic comet to be identified (by Edmund Halley) and the brightest of all recurring comets.
Halliburton, Richard (1900–39), U.S. explorer and writer.
Halloween, festival held on Oct. 31, the eve of All Saints' Day, a holiday of the Roman Catholic and Anglican churches held to honor all the saints.
Hallucinogenic drug, consciousness-altering drug that causes hallucinations or illusions, usually visual, together with personality and behavior changes.
Halo, in meteorology, luminous ring sometimes observed around the sun or the moon, caused by refraction and reflection of light by ice crystals in the atmosphere of the earth.
Halogen, any of the group of 5 elements consisting of fluorine, chlorine, bromine, iodine and astatine.
Halothane, chemical compound (C2HBrClF3) used as a general anesthetic.
Hals, Frans (c.1580–1666), Dutch portrait painter.
Halsey, William Frederick ‘Bull’, Jr. (1882–1959), U.S. admiral during World War II.
Ham, cured thigh, buttock, or leg of a hog.
Hamadryas See: Baboon.
Hamburg (1,660,700), historic seaport, capital city of Hamburg state; largest city in western Germany, near the mouth of the Elbe River.
Hamilcar Barca (d. c.228 B.C.), Carthaginian general, father of Hannibal.
Hamilton (pop. 2,000), capital and principal port of Bermuda, situated on Main Island.
Hamilton (pop. 599,800), city in the province of Ontario, Canada, built on the plain between a landlocked harbor on Lake Ontario and the 250-ft (76-m) Niagara escarpment.
Hamilton (pop. 62,368), industrial town in southwest Ohio on the Great Miami River, seat of Butler County.
Hamilton, Alexander (1775–1804), U.S. political leader, a founder of the country. He was George Washington's secretary during the American Revolution, later serving as a delegate to the Continental Congress (1782–83). A delegate (from New York) to the Constitutional Convention of 1787, he was a strong supporter of the Constitution and was instrumental in getting it adopted. A …
Hamilton, Alice (1869–1970), U.S. physician and social reformer.
Hamilton, Emma, Lady (1765–1815), celebrated English beauty who became the mistress of Lord Nelson and the subject of many portraits by leading artists.
Hamilton, Virginia (1936– ), U.S. author of children's books.
Hamites, peoples inhabiting eastern Africa, especially Somalia and Ethiopia, and northern Africa, where they are known as Berbers.
Hamlin, Hannibal (1809–91), U.S. vice president under Abraham Lincoln, 1861–65.
Hammarskjöld, Dag (1905–61), Swedish politician, UN secretary general 1953–61.
Hammer throw, Olympic sports event in which the athlete throws a 16-lb (7.26-kg) “hammer” (actually a metal sphere with a handle), spinning in place to gain momentum before releasing it.
Hammerstein, name of 2 U.S. theatrical producers.
Hammett, (Samuel) Dashiell (1894–1961), U.S. writer and left-wing political activist.
Hammond (pop. 93,700), industrial city in northwest Indiana, in the Calumet region, near Lake Michigan.
Hammurabi, or Hammurapi, sixth king of the first dynasty of Babylonia (r. 1792–50 B.C.).
Hampton Court Conference, meeting held at Hampton Court Palace, England, in 1604 to consider Puritan demands for reform in the Church of England, especially of the episcopal system of Church government and the Book of Common Prayer.
Hampton, Lionel (1913– ), U.S. jazz vibraphonist and bandleader.
Hampton Roads, natural harbor and port in southeast Virginia formed by the confluence of 3 rivers—the James, Nansemond, and Elizabeth—that flow into Chesapeake Bay.
Hampton Roads, Battle of See: Monitor and Merrimack.
Hampton Roads Conference, meeting held on Feb. 3, 1865 aboard the River Queen, anchored in Chesapeake Bay, in an attempt to end the Civil War.
Hampton University, private college in Hampton, Va., founded 1868 to educate freed slaves and later funded for the education of Native Americans.
Hampton, Wade (1818–1902), U.S. politician and soldier.
Hamster, any of various short-tailed rodents of Europe and Asia.
Hamsun, Knut (1859–1952), Norwegian novelist.
Han dynasty, dynasty that ruled China 202 B.C.–220 A.D.
Han Kao-tsu See: Liu Bang.
Hancock, John (1737–93), U.S. revolutionary leader, president of the Continental Congress (1775–77) and first signer of the Declaration of Independence.
Hancock, Winfield Scott (1824–86), U.S. general and politician.
Hand, Learned (1872–1961), U.S. jurist noted for his profoundly reasoned rulings in almost 3,000 cases.
Handball, court game played by 2 to 4 people.
Handel, George Friedrich (1685–1759), German-born composer who settled in England in 1712, one of the greatest composers of the baroque period.
Handicap, physical or mental disability, congenital or acquired, that inhibits a person from participating in normal life.
Handicraft, name given to the process of making objects by hand; also refers to the products of that process.
Handwriting on the wall, incident in the Old Testament (Book of Daniel).
Handy, W(illiam) C(hristopher) (1873–1958), U.S. songwriter, bandleader, and jazz composer.
Hanging Gardens of Babylon See: Seven Wonders of the Ancient World.
Hangzhou, or Hangchow (pop. 1,340,000), city of eastern China, capital of Zhejiang province.
Hankou See: Wuhan.
Hanna, Mark (1837–1904), U.S.
Hannibal (247–183? B.C.), Carthaginian general who almost defeated Rome in the Second Punic War (218–201 B.C.).
Hannibal (pop. 18,046), town in Marion county, northeastern Missouri, on the Mississippi River.
Hanoi (pop. 3,056,100), capital of North Vietnam (1954–76) and of united Vietnam since 1976.
Hanover, or Hannover, region of northwest Germany.
Hanover (pop. 514,400), or Hannover, city on the Leine River in northwest Germany, capital of the state of Lower Saxony.
Hanover, House of, reigning family of Hanover, in Germany, and of Great Britain (1714–1901).
Hansberry, Lorraine (1930–65), African American playwright and civil rights activist.
Hanseatic League, medieval confederation of North German towns and merchants organized to protect their trading interests in the Baltic Sea and throughout Europe.
Hansen's disease See: Leprosy.
Hanson, Howard (1896–1981), U.S. conductor, teacher, and composer in the Romantic tradition.
Hanson, John (1721–83), U.S. political leader, first president of the Congress of Confederation, under the Articles of Confederation (1781).
Hanukkah, Jewish holiday commemorating the rededication of the Temple of Jerusalem in 164 B.C. after Judas Maccabeus's victory over the Hellenic king Antiochus IV.
Hanyang See: Wuhan.
Hapsburg, House of See: Habsburg, House of.
Hara-kiri, or seppuku, ancient Japanese act of ceremonial suicide, in which a short sword was used to slash the abdomen from left to right, then upward.
Harappa See: Indus Valley civilization.
Harare (formerly Salisbury; pop. 656,000), capital and largest city of the Republic of Zimbabwe.
Harbin (pop. 2,830,000), city in northeast China on the Sungari River, capital of Heilongjiang province.
Hardening of the arteries See: Arteriosclerosis.
Harding, Warren Gamaliel (1865–1923), 29th president of the United States. Harding's administration was marred by scandals, and his imprudent political appointments and lack of personal decisiveness have made historians rank him as one of the weakest presidents in U.S. history. Harding studied law, sold insurance, and taught school before finding his vocation—journalism—…
Hardness, measure of the resistance of a substance to being scratched by another substance.
Hardy, Oliver See: Laurel and Hardy.
Hardy, Thomas (1840–1928), English novelist and poet.
Hare, any of various species (genus Lepus) of herbivorous mammals of the rabbit family, including the jackrabbit.
Hare Krishnas, popular name for members of a Hindu sect (the International Society for Krishna Consciousness), known for their orange robes, shaved heads, and public chanting of “Hare Krishna” in praise of the Hindu god Krishna.
Harebell See: Bluebell.
Harelip See: Cleft palate.
Hargreaves, James (1720?–78), British inventor of the spinning jenny (1764), a machine for spinning several threads at once.
Hari-kari See: Hara-kiri.
Harkins, William Draper (1873–1951), U.S. chemist who predicted the existence of the neutron (1927) and theorized the possibility of nuclear fusion: the combination of 4 hydrogen atoms to become 1 helium atom with a minute extra mass converted into energy.
Harlan, 2 associate justices of the U.S.
Harlem, neighborhood in the northern part of the borough of Manhattan, New York City.
Harlem Renaissance, period of cultural development among U.S. blacks, centered on Harlem, New York City, in the 1920s.
Harlequin snake See: Coral snake.
Harlow, Harry Frederick (1905–81), U.S. psychologist who studied the effects in monkeys of deprivation of maternal love and other social contact.
Harlow, Jean (1911–37), platinum-blonde U.S. film actress who began her career as a sex symbol and developed into a gifted comedienne.
Harmonic motion, vibrating or oscillating motion that repeats itself in equal time intervals, as in the motion of a swinging pendulum.
Harmonica, or mouth organ, musical instrument that contains a number of small metal reeds of graduated size enclosed in slots in a short narrow box.
Harmonics, basic compounds of a musical tone, consisting of the various vibrations of sound that produce what sounds like a single tone.
Harmonium, small reed organ with pedals for pumping air past the reeds.
Harmony, in music, the simultaneous sounding of 2 or more tones or parts; also the relation and progression of chords and the rules governing their relationship.
Harness racing, form of horse racing in which each horse draws a lightweight, two-wheeled cart (called a sulky) driven by a driver.
Harnett, William Michael (1848–92), Irish-born U.S. painter.
Harold, name of two kings of England.
Harold, kings of Norway.
Harp, musical instrument consisting of a number of strings of different lengths stretched across a frame.
Harper, Frances Ellen Watkins (1825–1911), African-American writer and lecturer.
Harpers Ferry (pop. 400), town in eastern West Virginia, site of a federal armory established by George Washington.
Harpsichord, keyboard instrument in which the strings are plucked by quills rather than hit by felt hammers as in a piano.
Harpy, in Greek mythology, birdlike monster with the head of a woman.
Harpy eagle, large bird of prey (Harpia harpyja) of the hawk family, native to tropical forests of the Western Hemisphere.
Harrier, breed of dog developed for fox and hare hunting, possibly as long ago as A.D. 1,000 Harriers stand about 21 in. (50 cm) tall and weigh 35 to 55 lbs (16 to 25 kg).
Harriman, family name of a father and son prominent in U.S. commerce and government. Edward Henry Harriman (1848–1909) was a railroad tycoon and stockbroker who, after financial struggles with J.J. Hill, joined with Hill and J.P. Morgan to create a holding company designed to prevent competition on the railroads. It was dissolved by the Supreme Court in 1904. His son, W(illiam) Averell Harr…
Harrington, James (1611–77), English philosopher best known for his Commonwealth of Oceana (1656), a treatise on the ideal state ruler.
Harris, Benjamin (1673–1716), English-American bookseller and writer, publisher of the first newspaper in America (1690).
Harris, Frank (1856–1931), British author best known for his biographies of Shakespeare, Oscar Wilde, and G.
Harris, Joel Chandler (1848–1908), U.S. southern journalist and regional author.
Harris, Patricia Roberts (1924–85), U.S. public official, first African-American woman to be a U.S. ambassador, to hold a cabinet post, and to serve as a director of a U.S. corporation.
Harris, Roy (1898–1979), U.S. composer.
Harrisburg (pop. 587,986), state capital of Pennsylvania and seat of Dauphin County.
Harrison, Benjamin (1726–91), American Revolutionary leader.
Harrison, Benjamin (1833–1901), 23rd president of the United States. Harrison, the grandson of President William Henry Harrison, gained the presidency at a time when labor unrest, agricultural depression, and fiscal controversies were beginning to shake the Republican party's hold over national affairs. After graduating from Miami University of Ohio in 1852, Harrison studied law in C…
Harrison, George See: Beatles.
Harrison, William Henry (1773–1841), 9th president of the United States. Harrison, a military hero and the first successful candidate of the Whig party, died 1 month after taking office—the briefest term of any U.S. chief executive. Harrison's father was a prominent figure in Virginia politics and a signer of the Declaration of Independence. The young Harrison attended Hampden…
Harsha, or Harshavardhana (A.D. 590?–47), king of northern India (606–47), patron of the arts, and writer.
Hart See: Red deer.
Hart, Gary Warren (1936– ), U.S. politician.
Hart, John (1711?–79), American Revolutionary leader.
Hart, Lorenz Milton (1895–1943), U.S. lyricist who collaborated with Richard Rodgers on 29 musical comedies.
Hart, Moss (1904–61), U.S. dramatist and director.
Harte, Bret (Francis Brett Harte; 1836–1902), U.S. writer whose short stories of frontier life helped create the mythology of the West.
Hartebeest, large antelope (genus Alcelaphus) with a long and narrow head and lyre-shaped horns.
Hartford (pop. 136,400), capital and largest city of Connecticut, situated near the center of the state on the Connecticut River.
Hartford Convention, assembly of Federalist delegates from Massachusetts, Connecticut, Rhode Island, and Vermont, held secretly in Hartford, Conn., Dec. 1814, to Jan. 1815.
Hartford, George Huntington (1833–1917), U.S. merchant, cofounder of the Great Atlantic and Pacific Tea Company (A&P).
Hartley, Marsden (1877–1943), U.S. artist who experimented with cubism and abstraction and later returned to impressionistic but realistic depictions of natural scenes.
Harun al-Rashid (ar-Rashid; 766–809), fifth Abbasid caliph of Baghdad (r. 786–809) whose empire extended from northern Africa to the Indus River in India.
Harunobu (Suzuki Harunobu; 1725–70), Japanese artist who perfected multi-colored printmaking.
Harvard, John (1607–38), U.S. cleric, first benefactor of Harvard College.
Harvard University, oldest university in the United States, founded by the General Court of Massachusetts in 1636.
Harvest mite See: Chigger.
Harvest moon, popularly, the full moon that occurs nearest to the time of the autumnal equinox (around Sept. 23).
Harvestman See: Daddy longlegs.
Harvey, William (1578–1657), British physician who pioneered modern medicine, discovering the circulation of blood.
Hashemite Dynasty, Arab royal family claiming descent from the grandfather of the prophet Muhammad, hereditary sharifs of Mecca from the 11th century until 1919.
Hashish, drug produced from a resin obtained from the top and the flowers of the hemp plant (Cannabis sativa).
Hasidism, Jewish pietistic movement, that can be divided into 3 distinct historical eras.
Haskalah (Hebrew, “enlightenment”), cultural movement that attempted to reform traditional Jewish customs.
Hassam, Childe (1859–1935), U.S. painter and graphic artist.
Hassan II (1929– ), king of Morocco since 1961.
Hastie, William Henry (1904–76), first black judge appointed to the U.S.
Hastings, Battle of, first decisive military encounter of the Norman conquest of England, fought between the troops of King Harold of England and Duke William of Normandy on Oct. 14, 1066.
Hastings, Warren (1732–1818), first governor-general of British India (1774–84).
Hat, head covering, usually with a brim all around it, as distinct from a brimless cap or hood.
Hatch Act, U.S. law sponsored by Sen.
Hatcher, Richard Gordon (1933– ), U.S. politician.
Hathor, or Athyr, in ancient Egyptian religion, goddess of the sky.
Hatshepsut (d. 1481 B.C.), queen of Egypt, 18th dynasty.
Hauptmann, Gerhart (1862–1946), German author and playwright who pioneered naturalism in the German theater.
Hausa, people of northwest Nigeria and neighboring Niger, numbering about 9 million, predominantly Muslim since the 14th century.
Havana (pop. 2,100,000), capital and largest city of Cuba, on the Gulf of Mexico.
Havel, Václav (1936– ), Czech playwright and political leader, elected president of Czechoslovakia in 1989.
Haversian canals, minute passages in the outer bone layers.
Haw See: Hawthorn.
Hawaii, fiftieth state of the United States, a chain of 8 major and more than 100 minor islands in the central Pacific Ocean, about 2,100 mi (3,380 km) from the U.S. mainland. Hawaii's islands are of volcanic origin, although all but the 8 major islands at the southeastern end of the chain have been reduced to coral atolls and small rock outcroppings. The largest island, Hawaii, which has g…
Hawaii Volcanos National Park, on Hawaii Island, established 1916, has among the largest and most active volcanos in the world.
Hawaiian goose See: Nene.
Hawaiian honeycreeper, any of a family (Drepanididae) of small songbirds exclusive to Hawaii.
Hawk moth, member of the Sphinx moth family.
Hawke, Robert James Lee (1929– ), prime minister of Australia 1983–90.
Hawking, Stephen William (1942– ), British theoretical physicist and cos-mologist who has applied general relativity and quantum mechanics to the theory of black holes in novel ways and produced results of great originality.
Hawkins, Coleman (1904–69), U.S. tenor saxophonist.
Hawkins, Sir John (1532–95), British admiral.
Hawks, Howard (1896–1977), U.S. film director who specialized in sharp dialogue and visual clarity.
Hawthorn, any of several hundred species of shrubs and small trees (genus Crataegus) of the rose family.
Hawthorne, Nathaniel (1804–64), major U.S. novelist and short story writer whose novels The Scarlet Letter (1850) and The House of the Seven Gables (1851) are considered masterpieces of psychological portraiture, capturing the dark atmosphere of Puritan New England.
Hay fever, common allergy to the pollen of grasses and trees.
Hay-Herrán Treaty, agreement (1903) between the United States and Colombia that would have given the United States rights to the Panama Canal Zone.
Hay, John Milton (1838–1905), U.S. politician and author, secretary to President Lincoln (1860–65).
Hay-Pauncefote Treaties, agreements between the United States and Great Britain negotiated in 1899 and 1901, giving the United States the sole right to construct and control the proposed Panama Canal.
Hayakawa, S(amuel) l(chiyé) (1906– ), Canadian-born U.S. language expert, specializing in the study of semantics.
Hayden, Melissa (Mildred Herman; 1923– ), Canadian-born U.S. ballet dancer, teacher, and director.
Haydn, Franz Joseph (1732–1809), Austrian composer who established the accepted classical forms of the symphony, string quartet, and piano sonata.
Hayes, Helen (Helen Hayes Brown; 1900–93), U.S. actress.
Hayes, Rutherford Birchard (1822–93), 19th president of the United States. Hayes, who won office in a bitterly contested election, began his term during a period of sectional and economic crisis. By the time he left office, economic prosperity had been restored and Reconstruction in the South brought to a close. These accomplishments carried a high price, however: For Southern blacks, the e…
Haymarket Square Riot, violent confrontation between labor organizers and police in Chicago's Haymarket Square on May 4, 1886.
Hayne, Robert Young (1791–1839), U.S. politician.
Haywood, William Dudley (1869–1928), U.S. labor leader and principal organizer of the Industrial Workers of the World (1905).
Hazardous wastes, chemicals and their byproducts that are dangerous to humans or pollute the environment.
Hazel, shrub or small tree (genus Corylus) that produces catkins early in the spring.
Hazlitt, William (1778–1830), English literary critic and essayist.
Head Start, U.S. government program established in 1964 by the Economic Opportunity Act to prepare disadvantaged children for school and to involve parents and local communities in the effort.
Headache, common ailment and manifestation of many diseases and disorders involving the brain, eyes, nose, throat, teeth, and ears.
Headhunter, one who cuts off the head of a defeated enemy to preserve it as a trophy or for religious reasons or in the belief that it strengthens one's own tribe while weakening the enemy.
Headphones, device that allows a person to hear sound reproductions in private.
The practices that help a person to maintain health —including proper nutrition, exercise, and cleanliness— are called hygiene.
Health, Education, and Welfare, Department of See: Health and Human Services, U.S.
Health and Human Services, U.S.
Health Insurance, National (NHI), program that provides health care for a country's citizens.
Health, National Institutes of See: National Institutes of Health.
Health, public See: Public health.