n. Any substance produced by, or taking part in, a metabolic reaction.
the GNU version of the Collaborative International Dictionary of English
n. A product of metabolism; a substance produced by metabolic action, as urea.
The Century Dictionary and Cyclopedia
n. A product of or substance resulting from metabolism, especially from retrograde metabolism, or catabolism.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. any substance involved in metabolism (either as a product of metabolism or as necessary for metabolism)
Word Usage
"First they took cerebral spinal fluid from 132 juvenile rhesus monkeys and analyzed it for a serotonin metabolite, called 5-HIAA, that’s considered a reliable indicator of how much serotonin the nervous system is processing."