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con·cave

(kŏn-kāv, kŏnkāv′)

adj.

Curved like the inner surface of a sphere.

A concave surface, structure, or line.

tr.v. con·caved, con·cav·ing, con·caves

To make concave.

[Middle English, from Latin concavus : com-, intensive pref.; see COM- + cavus, hollow; see keuə- in the Appendix of Indo-European roots.]

con·cavely adv.

con·caveness n.

(click for a larger image)

concave

left to right: biconcave,

plano-concave, and

concavo-convex lenses

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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