pol·y·mer 
(pŏlə-mər)
(pŏlə-mər)n.
Any of numerous natural and synthetic compounds of usually high molecular weight consisting of up to millions of repeated linked units, each a relatively light and simple molecule.
[Greek polumerēs, consisting of many parts : polu-, poly- + meros, part; see (s)mer-2 in the Appendix of Indo-European roots.]