vitamin A

noun

a fat-soluble aliphatic alcohol, CHOH, found in fish-liver oil, egg yolk, butter, etc. or derived from carotene in carrots and other vegetables: a deficiency of this vitamin results in night blindness, a general susceptibility to infections, and degeneration of epithelial tissue: it usually occurs in two forms, vitamin A1, having the formula above, and vitamin A2, CHOH