/ Thesaurus / L Synonyms of light tight Find synonyms for: Adjective1. lightproof, light-tight, opaque (vs. clear)usage: not penetrable by light; "lightproof containers"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language