vitamin A

noun

1. a yellow, fat-soluble, solid terpene alcohol, C 20 H 30 O, 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.

vitamin A

noun

1. 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 Also calledvitamin A1retinol

vitamin A

1. A fat-soluble vitamin important for normal vision, tissue growth, and healthy skin. It is found in fish-liver oils, milk, green leafy vegetables, and red, orange, and yellow vegetables and fruits. A deficiency of vitamin A in humans causes poor vision at night and damage to the skin and mucous membranes. Also called retinol. Chemical formula: C 20 H 30 O.

Word History and Origins

Origin of vitamin A¹

First recorded in 1920–25