- a yellow, fat-soluble, solid terpene alcohol, C20H30O, obtained from carotene and occurring in green and yellow vegetables, egg yolk, etc.: essential to growth, the protection of epithelial tissue, and the prevention of night blindness.
- a fat-soluble yellow unsaturated alcohol occurring in green and yellow vegetables (esp carrots), butter, egg yolk, and fish-liver oil (esp halibut oil). It is essential for the prevention of night blindness and the protection of epithelial tissue. Formula: C 20 H 30 O