Phycobilins

Part of speech: noun

Definitions

1. A type of accessory pigment found in certain algae and cyanobacteria that assists in capturing light for photosynthesis
2. These pigments, including phycoerythrin and phycocyanin, enhance light absorption in aquatic plants, particularly in deeper waters
3. Used by some photosynthetic organisms, these colored compounds play a crucial role in light energy conversion for growth and metabolism

Etymology: "Phycobilins" is the plural of "phycobilin," a family of light-absorbing pigments found in algae and cyanobacteria. The name is a scientific coinage built from New Latin pieces: "phyco-," from Greek "phykos," meaning seaweed or alga, and "bilin," from the Latin "bilis," meaning bile. The pigments are chemically related to bile pigments, which is why the second half of the word points to the digestive fluid. The name is a little tangled. Read on the surface, "phycobilin" looks like "phyco-" plus "bili-" plus "-in," with "bili-" taken from bile. Yet the American Heritage Dictionary holds that "bilin" was back-formed from "phycobilin," so the chain ran the other way: the algal pigment name came first, and "bilin" was carved out of it afterward. The "-in" ending is the common chemical suffix used for many named substances.