Edema, or dropsy, swelling of bodily tissues due to the accumulation of fluid. It most commonly affects the lower parts of the body, such as the ankles and lower part of the abdomen. Edema is generally the sign of a serious disease. A failing heart may cause edema because it cannot pump blood fast enough to carry away body fluids efficiently. Edema may be a sign of liver or kidney disease or of preeclampsia (toxemia that may occur late in pregnancy). The potbellies of starving children are also cases of edema. The basic cause of the edema must be removed to cure it, but the physician may also prescribe diuretic drugs to rid the body of excess water.