unfastening

(noun) loosening the ties that fasten something. Synonyms: untying, undoing. Example: "The tying of bow ties is an art; the untying is easy."

(verb) cause to become undone. Synonyms: unfasten. Example: "Unfasten your belt."

(verb) become undone or untied. Synonyms: unfasten. Example: "The shoelaces unfastened."