fas ‧ ten ‧ er /ˈfɑːs ə nə $ ˈfæs ə nər/ BrE AmE ( also fas‧ten‧ing /ˈfaːs ə nɪŋ $ ˈfæ-/) noun [countable]
[ Word Family: verb : ↑ fasten ≠ ↑ unfasten ; noun : ↑ fastener ]
1 . something that you use to join something together, such as a button on a piece of clothing:
shoes with velcro fasteners
2 . something that is used to keep a door, window etc firmly shut SYN latch