side chain

WordReference Random House Unabridged Dictionary of American English © 2025

side′ chain′, [Chem.]

1. Chemistry an open chain of atoms attached to an atom of a larger chain, or to a ring. Also called lateral chain. 

• 1900–05

Collins Concise English Dictionary © HarperCollins Publishers::

side chain noun

1. a group of atoms bound to an atom, usually a carbon, that forms part of a larger chain or ring in a molecule