Synonyms for trench Found 6 synonyms across 3 meanings for “trench”. a long steep-sided depression in the ocean floor (noun) deep impinge or infringe upon (verb) impingeencroachentrench cut a trench in, as for drainage (verb) ditch Explore Related Words Rhymes with trenchSynonyms for deepSynonyms for impingeSynonyms for encroachSynonyms for entrenchSynonyms for ditch Synonym Finder | Rhyme Finder | Poetry Editor