/ Thesaurus / S Synonyms of spectrum line Find synonyms for: Noun1. spectrum line, lineusage: an isolated component of a spectrum formed by radiation at a uniform frequencyWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language