means The act of removing or pulling back from something — money from an account, a substance from the body, a person from a situation — and the often uncomfortable aftermath of that removal.

from Built from "withdraw," itself a Middle English stitching of "with-" (here meaning "back, away," an old sense now mostly lost) and "draw" (to pull). So at root it's literally "to pull away." The "-al" suffix, borrowed from French and Latin habits of noun-making, turns the act into a thing. The medical and addiction sense — the body's protest when a substance is drawn away — is a much later specialization of that plain old "pulling back."