Homopolymer that is composed of macromolecules comprising blocks that have at least one constitutional or configurational feature which is not present in the adjacent portions.
Source:
PAC, 2016, 88, 1073. 'Source-based nomenclature for single-strand homopolymers and copolymers (IUPAC Recommendations 2016)' on page 1078 (https://doi.org/10.1515/pac-2015-0702)