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ligand

[lahy-guh nd, lig-uh nd]
noun
  1. Biochemistry. a molecule, as an antibody, hormone, or drug, that binds to a receptor.
  2. Chemistry. a molecule, ion, or atom that is bonded to the central metal atom of a coordination compound.
Compare complexing agent.

Origin of ligand

1945–50; < Latin ligandus, gerund of ligāre to bind, tie
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ligand

ligand

noun
  1. chem an atom, molecule, radical, or ion forming a complex with a central atom

Word Origin for ligand

C20: from Latin ligandum, gerund of ligāre to bind
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
Word Origin and History for ligand
n.

1952, from Latin ligandus, gerundive of ligare "to bind" (see ligament).

Online Etymology Dictionary, © 2010 Douglas Harper
ligand in Medicine

ligand

[lī′gənd, lĭg′ənd]
n.
  1. An ion, a molecule, or a molecular group that binds to another chemical entity to form a larger complex.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.