/ Dictionary / Index P pentatonism: Meaning and Definition of Find definitions for: pen•ta•ton•ism Pronunciation: (pen'tu-tō-niz"um, -to-), [key] — n. Music. the use of a five-tone scale. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pentatonic scale pentavalent Related Content Daily Word Quiz: resilient Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language