ˈkripˌtän, -_tən noun
( -s )
Etymology: Greek, neuter of kryptos hidden — more at crypt
: a colorless inert gaseous element that occurs in air to the extent of about one part per million by volume and in gases from thermal springs and other natural gases, that is obtained by separating from liquid air, and that is used in electric lamps (as small quartz lamps for extremely brilliant illumination) — symbol Kr ; see element table