retinoic acid(redirected from vitamin A1 acid)
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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.