'Trireme' definitions:

Definition of 'trireme'

(from WordNet)
noun
Ancient Greek or Roman galley or warship having three tiers of oars on each side

Definition of 'Trireme'

From: GCIDE
  • Trireme \Tri"reme\, n. [L. triremis; tri- (see Tri-) + remus an oar, akin to E. row. See Row to propel with an oar.] (Class. Antiq.) An ancient galley or vessel with tree banks, or tiers, of oars. [1913 Webster]