/ Dictionary / Index S space sickness: Meaning and Definition of Find definitions for: space' sick"ness Pronunciation: [key] — Pathol. Pathol. a complex of symptoms including nausea, lethargy, headache, and sweating, occurring among astronauts under conditions of weightlessness. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. space shuttle orbiter space stage Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language