1432, "healthy condition," from M.Fr. sanité "health," from L. sanitas "health, sanity," from sanus "healthy, sane." Meaning "soundness of mind" first attested 1602.
Main Entry: san·i·ty Pronunciation: 'san-&t-E Function: noun Inflected Form: plural-ties : the quality or state ofbeing sane; especially: soundness or health of mind