Noun: unfastening ,ún'fã-su-ning- Loosening the ties that fasten something
"the tying of bow ties is an art; the unfastening is easy";
- untying, undoing
Verb: unfasten ,ún'fã-sun- Become undone or untied
"The shoelaces unfastened"
- Cause to become undone
"unfasten your belt"
Type of: laxation, loosening, open, open up, undo
Antonym: fasten