1) Abnormally low potassium concentration in the blood; may result from excessive potassium loss by the renal or gastrointestinal route, from decreased intake, or from transcellular shifts; manifested clinically by neuromuscular disorders ranging from weakness to paralysis, by electrocardiographic abnormalities, and by renal and gastrointestinal disorders.

2) Hypokalemia; lower than normal levels of potassium in the circulating blood.

3) A deficiency of potassium in the blood -- called also hypopotassemia.