1542, from L. rostrum,
name of the platform stand for public speakers in the Forum in ancient Rome. It was decorated with the beaks of ships taken in the first naval victory of the Roman republic, over Antium, in 338 B.C.E., and the word's older sense is "end of a ship's prow," lit. "beak, muzzle, snout," originally "means of gnawing," instrument noun form of rodere
"to gnaw" (see rodent
). Cf. claustrum
"lock, bar," from claudere
"to shut." Extended sense of any platform for public speaking is first recorded 1766. Plural form is rostra.