Yours, Etc.: Origins and Uses of 8 Sign-Offs
1630s, back-formation from amputation or else from Latin amputatus, past participle of amputare "to cut off, to prune." Related: Amputated; amputating.
amputate am·pu·tate (ām'pyu-tāt')v. am·pu·tat·ed, am·pu·tat·ing, am·pu·tates To cut off a part of the body, especially by surgery.