Any of various yellow pigments occurring in the leaves of plants and giving young shoots and late autumn leaves their characteristic color. This color is masked by chlorophyll when the leaf is mature. Xanthophylls aid in the absorption of light by capturing certain wavelengths not captured by chlorophyll and rapidly transferring the energy to chlorophyll by boosting one of its electrons to a higher energy level. Xanthophylls are carotenoids, differing from carotenes in having one or more oxygen-containing groups attached. See also carotene.