Breadcrumb Home > Thesaurus > U Synonyms of unfasten Find synonyms for: Verb 1. unfasten, undo usage: cause to become undone; "unfasten your belt" 2. unfasten, open, open up usage: become undone or untied; "The shoelaces unfastened" WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of unfasten (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: rosarium Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language