Polymerize

1. v. i. To change into another substance having the same atomic proportions, but a higher molecular weight; to undergo polymerization; thus, aldehyde polymerizes in forming paraldehyde.
2. v. t. To cause polymerization of; to produce polymers from; to increase the molecular weight of, without changing the atomic proportions; thus, certain acids polymerize aldehyde.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.