unfastening

Từ điển WordNet v3.1 - WordNet Dictionary

noun

loosening the ties that fasten something
- the tying of bow ties is an art; the untying is easy
• Syn:
untying, undoing
• Derivationally related forms:
unfasten, undo (for: undoing), untie (for: untying)
• Hypernyms:
loosening, laxation