Synonyms for heater Found 5 synonyms across 2 meanings for “heater”. device that heats water or supplies warmth to a room (noun) warmer (baseball) a pitch thrown with maximum velocity (noun) fastballsmokehummerbullet Explore Related Words Rhymes with heaterSynonyms for warmerSynonyms for fastballSynonyms for smokeSynonyms for hummerSynonyms for bullet Synonym Finder | Rhyme Finder | Poetry Editor