/ Dictionary / Index S space cadet: Meaning and Definition of Find definitions for: space' cadet" Pronunciation: [key] — Slang. Slang. a person who appears to be in his or her own world or out of touch with reality. a person who behaves oddly or seems stupefied or remote because of the influence of drugs; druggie. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. spaceborne space capsule Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language