What does "unfasten" mean?

To detach from any connecting agency or link; to disconnect.

What is a synonym for "unfasten"?

Common synonyms include: undo, cast off, degage, dequip gear, detach, detach.

Pronounced //ʌnˈfɑːs(ə)n//.

/ʌnˈfɑːs(ə)n/ verb

verb ·Moderate ·College level

Verb

1
To detach from any connecting agency or link; to disconnect. transitive
"He doth unfasten so and shake a friend."
2
become undone or untied wordnet
3
To come unloosed or untied. intransitive
4
cause to become undone wordnet

"Tom tried to unfasten his seatbelt."

From un- + fasten.