Pronunciation: (lī'gund, lig'und), [key]
1. Biochem.a molecule, as an antibody, hormone, or drug, that binds to a receptor.
2. Chem.a molecule, ion, or atom that is bonded to the central metal atom of a coordination compound. Cf. complexing agent.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.