button up

button up (third-person singular simple present buttons up, present participle buttoning up, simple past and past participle buttoned up)

1. (transitive) To fasten with a button or buttons.

   Button up your shirt cuff. It has come undone

2. (intransitive) To fasten all the buttons on a coat, or similar item of clothing, to keep warm.

   Button up well. It's freezing outside today.

• The object in 1 can come before or after the particle. If it is a pronoun, then it must come before the particle.