/ Dictionary / Index P population pyramid: Meaning and Definition of Find definitions for: popula'tion pyr"amid Pronunciation: [key] — Sociol. Sociol. a graph showing the distribution of a population by sex, age, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. population pressure Populism Related Content Daily Word Quiz: fervor Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language