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English definition of “unfasten”


verb [I or T]     /ʌnˈfɑː.sən/ US  /-ˈfæs-/
to release or open something that is fixed or closed: I can't unfasten this button/belt. This blouse unfastens (= can be unfastened) at the back.Unfastening and opening
(Definition of unfasten verb from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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