/ Dictionary / Index P picogram: Meaning and Definition of Find definitions for: pi•co•gram Pronunciation: (pē'ku-gram", pī'-), [key] — n. one trillionth of a gram. Abbr.: pg Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. picofarad picoline Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language