A macromolecule with one or more species of block connected to the main chain (backbone) as side chains, these side chains having constitutional or configurational features that differ from those in the main chain.
Source:
PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2293 (https://doi.org/10.1351/pac199668122287)