The Collaborative International Dictionary of English v.0.48:
Unhook \Un*hook"\, v. t. [1st pref. un- + hook.] To loose from a hook; to undo or open by loosening or unfastening the hooks of; as, to unhook a fish; to unhook a dress. [1913 Webster]WordNet (r) 3.0 (2006):
unhook v 1: take off a hook [ant: hook]