retinoid /ret″inoid/ [L, rete, net; Gk, eidos, form] , 1. resembling the retina. 2. pertaining to any of a group of compounds whose molecules contain 20 carbon atoms structurally related to retinal, retinol, and other substances, some of which exhibit vitamin A activity. Retinoid analogs have been used in the prevention and treatment of various skin cancers and treatment of the digestive and respiratory tracts. 3. resinlike or having a resemblance to resin.
