button up

Definition of button up 

transitive verb

1 : to close tightly and securely a tank buttoned up and ready for action

2 : to carry to completion button up an order or assignment

3 : to bring to complete and final decision or irrevocable settlement

intransitive verb

: to become mum

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Britannica English: Translation of button up for Arabic Speakers

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playful or foolish behavior

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