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chlo·ro·phyll

(klôrə-fĭl)

Any of a group of green pigments that capture light energy used as the energy source in photosynthesis and that are found in the chloroplasts of plants and other photosynthetic organisms such as cyanobacteria, especially:

a. A waxy blue-black microcrystalline green-plant pigment, C₅₅H₇₂MgN₄O₅, with a characteristic blue-green alcohol solution. Also called chlorophyll a.

b. A similar green-plant pigment, C₅₅H₇₀MgN₄O₆, having a brilliant green alcohol solution. Also called chlorophyll b.

chlo′ro·phyllous adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

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Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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