either of a pair of connected metal rings that can be locked about the wrists, as in restraining a prisoner or fastening him to a policeman: usually used in pl.
to put handcuffs on; manacle
to check or hinder the activities of
See handcuff in American Heritage Dictionary 4
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.