/ Dictionary / Index P pollen tube: Meaning and Definition of Find definitions for: pol'len tube" Pronunciation: [key] — Bot. Bot. the protoplasmic tube that is extruded from a germinating pollen grain and grows toward the ovule. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pollen sac pollera Related Content Daily Word Quiz: dissonant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language