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a·cap·ni·a

(ā-kăpnē-ə)

A condition marked by an unusually low concentration of carbon dioxide in the blood and tissues.

[New Latin, from Latin acapnus, without smoke (which contains carbon dioxide), from Greek akapnos : a-, not; see A-¹ + kapnos, smoke.]

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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