carotene

noun

Etymology: Etymology tree English car(r)ot English -ene English carotene From car(r)ot + -ene.

1. A class of tetraterpene plant pigments; they vary in colour from yellow, through orange to red, this colour originating in a chain of alternating single and double bonds.
2. Specifically, a number of isomers of tetraterpene hydrocarbons, C₄₀H₅₆, (especially beta-carotene), present in carrots etc, which are converted into vitamin A in the liver.