/ Dictionary / Index P plant louse: Meaning and Definition of Find definitions for: plant' louse" Pronunciation: [key] aphid. any of various related insects having similar habits. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. plantlet plant pathology Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language