ˈzēˌnän, ˈzeˌnän noun
( -s )
Etymology: Greek, neuter of xenos strange
: a heavy colorless inert gaseous element that occurs in air to the extent of about one part in 20 million by volume and in gases from hot springs, that is obtained along with krypton from liquid air, and that is used in thyratrons and specialized electric lamps — symbol Xe ; see element table