say it: TRAHY-reem
trireme is a noun meaning "ancient Greek or Roman galley or warship having three tiers of oars on each side". It carries one recorded sense.
ancient Greek or Roman galley or warship having three tiers of oars on each side
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for trireme come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.