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ros·trum (rŏstrəm, rôstrəm)
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n. pl. ros·trums or ros·tra (rŏstrə, rôstrə)
1. A dais, pulpit, or other elevated platform for public speaking.
2.
a. The curved, beaklike prow of an ancient Roman ship, especially a war galley.
b. The speaker's platform in an ancient Roman forum, which was decorated with the prows of captured enemy ships.
3. Biology A beaklike projection, especially:
a. An anterior projection of an insect's or an arachnid's mouthparts, of the upper jaw of a cetacean, or of the cephalothorax of a crustacean.
b. A beaklike projection of a plant part, as the fruit of a geranium.
[Latin rōstrum, beak; see rēd- in the Appendix of Indo-European roots.]
(click for a larger image)
rostrum
of a weevil
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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