/ Dictionary / Index C Castro Valley: Meaning and Definition of Find definitions for: Cas'tro Val'ley Pronunciation: (kas'trō), [key] a town in W California, near San Francisco Bay. 44,011. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Castrop-Rauxel cast steel Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language