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pin·na

(pĭnə)

n. pl. pin·nae (pĭnē) or pin·nas

1. Botany A leaflet or primary division of a pinnately compound leaf.

2. Zoology A feather, wing, fin, or similar appendage.

3. Anatomy See auricle.

[Latin, feather; see pet- in the Appendix of Indo-European roots.]

pinnal adj.

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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