/ Dictionary / Index I Imperial Valley: Meaning and Definition of Find definitions for: Impe'rial Val'ley Pronunciation: [key] an irrigated agricultural region in SE California, adjacent to Mexico, formerly a part of the Colorado Desert: it is largely below sea level and contains the Salton Sink. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. imperial presidency imperil Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language