hand·cuff (hăndʹkŭf')n. A restraining device consisting of a pair of strong, connected hoops that can be tightened and locked about the wrists and used on one or both arms of a prisoner in custody; a manacle. Often used in the plural.tr.v. hand·cuffed, hand·cuff·ing, hand·cuffs 1. To restrain with or as if with handcuffs. 2. To render ineffective or impotent. See Synonyms at hamper1.