unclasp

verb (used with object)

1. to undo the clasp or clasps of; unfasten.
2. to release from the grasp: to unclasp a sword handle.

verb (used without object)

3. to become unclasped, as the hands or arms.
4. to release or relax the grasp.

verb

1. (tr) to unfasten the clasp of (something)
2. to release one’s grip (upon an object)