/ Thesaurus / S Synonyms of stiff upper lip Find synonyms for: Noun1. stiff upper lip, self-restraint, temperatenessusage: self-restraint in the expression of emotion (especially fear or grief); "the British like to keep a stiff upper lip"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: illegible Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language