In Dornan's telling, Clinton was a "self-indulgent hedonist and phony," a dabbler in drugs, a letch.
1550s, probably a frequentative of dab. Original meaning was "wet by splashing;" modern figurative sense of "do superficially" first recorded 1620s. Related: Dabbled; dabbling. An Ellen Dablewife is in the Lancashire Inquests from 1336.