c. 1300, drippen, "to fall in drops; let fall in drops," from Old English drypan, also dryppan, from Proto-Germanic *drupjanan (source also of Old Norse dreypa, Middle Danish drippe, Dutch druipen, Old High German troufen, German triefen), perhaps from a PIE root *dhreu-. Related to droop and drop. Related: Dripped; dripping.
mid-15c., drippe, "a drop of liquid," from drip (v.). From 1660s as "a falling or letting fall in drops." Medical sense of "continuous slow introduction of fluid into the body" is by 1933. The slang meaning "stupid, feeble, or dull person" is by 1932, perhaps from earlier American English slang sense "nonsense" (by 1919).