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ret·i·no·ic acid

(rĕt′n-ōĭk)

1. A vitamin A derivative, C₂₀H₂₈O₂, that serves as a regulator of morphogenesis and functions in the growth and development of bone and the maintenance of epithelium.

2. Either of two isomers of this compound, tretinoin or isotretinoin, that are used as drugs chiefly to treat acne. In both senses also called vitamin A acid.

[RETIN(OL) + -OIC.]

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:

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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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