Word Study
xanthophyll
CIDE DICTIONARY
xanthophyll, n. [Xantho- + Gr. fy`llon leaf.].
A yellow coloring matter found in yellow autumn leaves, and also produced artificially from chlorophyll; -- formerly called also phylloxanthin . [1913 Webster]
OXFORD DICTIONARY
xanthophyll, n. any of various oxygen-containing carotenoids associated with chlorophyll, some of which cause the yellow colour of leaves in the autumn.
Etymology
as XANTHIC + Gk phullon leaf
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