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ex·ap·ta·tion

(ĕg′zăp-tāshən)

n.
Biology

The utilization of a structure or feature for a function other than that for which it was developed through natural selection.

[EX- + (AD)APTATION.]

ex·apted adj.

ex·aptive 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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