/ Dictionary / Index P polybutylene: Meaning and Definition of Find definitions for: pol•y•bu•tyl•ene Pronunciation: (pol"ē-byt'l-ēn"), [key] — n. Chem. any of several polymers of butylene, used chiefly in the manufacture of lubricants and synthetic rubber. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: polybutylene (Thesaurus) polybutadiene polycarbonate Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language