means A polymer is a large molecule built from many small, repeating units chained together, forming materials from plastics and rubber to proteins and DNA.

from Coined in the 19th century from the Greek 'polys' (many) plus 'meros' (part) — literally 'many parts.' The Swedish chemist Jöns Jacob Berzelius is credited with introducing the term, though his original sense differed from how we use it today; only later did 'polymer' settle into meaning a molecule made of many repeated subunits, called 'monomers' (single parts) from the same Greek roots.