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English definition of “unfasten”


verb [I or T] uk   /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 from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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