from
The Collaborative International Dictionary of English v.0.48
Chlorophyll \Chlo"ro*phyll\, n. [Gr. chlwro`s light green +
fy`llon leaf: cf. F. chlorophylle.]
1. (Bot.) Literally, leaf green; a green granular matter
formed in the cells of the leaves (and other parts exposed
to light) of plants, to which they owe their green color,
and through which all ordinary assimilation of plant food
takes place. Similar chlorophyll granules have been found
in the tissues of the lower animals. [Written also
{chlorophyl}.]
[1913 Webster]
2. any of a group of green pigments found in photosynthetic
organisms. {Chlorophyll a} and {chlorophyll b} are found
in higher plants and green algae; {chlorophyll c} is found
in certain types of marine algae. Chemically, it has a
porphyrin ring with a magnesium ion bound to the four
central nitrogens, and has a phytyl side chain. It is
essential for photosynthesis in most plants. {Chlorophyll
a} has formula {C55H72N4O5Mg}.
Syn: chlorophyll.
[WordNet 1.5]