/ Thesaurus / B Synonyms of box up Find synonyms for: Verb1. box in, box up, enclose, hold in, confineusage: enclose or confine as if in a boxWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language