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porphyrin

[pawr-fuh-rin]
noun Biochemistry.
  1. a dark red, photosensitive pigment consisting of four pyrrole rings linked by single carbon atoms: a component of chlorophyll, heme, and vitamin B12.

Origin of porphyrin

1905–10; < Greek porphýr(a) purple + -in2
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for porphyrin

porphyrin

noun
  1. any of a group of pigments occurring widely in animal and plant tissues and having a heterocyclic structure formed from four pyrrole rings linked by four methylene groups

Word Origin for porphyrin

C20: from Greek porphura purple, referring to its colour
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
porphyrin in Medicine

porphyrin

[pôr′fə-rĭn]
n.
  1. Any of various heterocyclic compounds, derived from pyrrole, that occur universally in protoplasm, contain a central metal atom, and provide the foundation structure for hemoglobin, chlorophyll, and certain enzymes.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
porphyrin in Science

porphyrin

[pôr′fə-rĭn]
  1. Any of various organic pigments containing four pyrrole rings bonded to one another. The rings form the corners of a large flat square, in the middle of which is a cavity that often contains a metal atom. Porphyrins occur universally in protoplasm and function with bound metals such as iron in hemoglobin and magnesium in chlorophyll.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.