/ Thesaurus / S Synonyms of seal in Find synonyms for: Verb1. lock in, seal in, confineusage: close with or as if with a tight seal; "This vacuum pack locks in the flavor!"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language