1. an orange-yellow to red crystalline pigment, C40H56, found in animal tissue and certain plants, such as carrots and squash. it exists in several isomeric forms and is converted to vitamin A in the liver.

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.

1. an orange isomer of an unsaturated hydrocarbon found in many plants; is converted into vitamin A in the liver
2. yellow or orange-red fat-soluble pigments in plants