/ Dictionary / Index P pilot plant: Meaning and Definition of Find definitions for: pi'lot plant" Pronunciation: [key] an experimental industrial plant in which processes or techniques planned for use in full-scale operation are tested in advance. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pilot light pilot raise Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language