unfasten
- v cause to become undone
unfasten your belt - v become undone or untied
The shoelaces unfastened
- Captain Perlas made a feeble effort to unfasten his seat belt.
- If your little Houdini likes to unfasten a restraint now and again, you might hear, "Warning: child climbing out.
- I wouldn't make it easy for a state to unfasten itself; we should require that a two-thirds majority of voters agree.