monomeric unit (monomer unit, mer)

The largest constitutional unit contributed by a single monomer molecule to the structure of a macromolecule or oligomer molecule.
Note:
The largest constitutional unit contributed by a single monomer molecule to the structure of a macromolecule or oligomer molecule may be described as either monomeric, or by monomer used adjectivally.
Source:
PAC, 1996, 68, 2287 (Glossary of basic terms in polymer science (IUPAC Recommendations 1996)) on page 2290