/ Thesaurus / L Synonyms of living substance Find synonyms for: Noun1. protoplasm, living substance, substanceusage: the substance of a living cell (including cytoplasm and nucleus)WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: grimace Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language