/ Dictionary / Index P Pleasanton: Meaning and Definition of Find definitions for: Pleas•an•ton Pronunciation: (plez'un-tun), [key] — n. a town in W California. 35,160. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Pleasant Island pleasantry Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language