A galley-type Grecian vessel with fifty oars.(noun)
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Use "penteconter" in a sentence
"The half company is technically called a pentecostys, and a quarter company an enomoty, and the officers in charge of them respectively penteconter and enomotarch."
"The most common galley at Aulis was probably the penteconter, a fifty-oared ship about ninety feet long, with twenty-five rowers sitting along each side of the hull."
"For now, we need note the presence of only one other kind of oared ship in both fleets of 480 B.C.: the penteconter."