/ Dictionary / Index L Lost Pleiad: Meaning and Definition of Find definitions for: Lost' Ple'iad. Pronunciation: [key] See under(def. 1). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lost motion lost river Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language