Main Entry: xe·non

Pronunciation: \ˈzē-ˌnän, ˈze-\

Function: noun

Etymology: Greek, neuter of xenos strange

Date: 1898

: a heavy colorless and relatively inert gaseous element that occurs in air as about one part in 20 million and is used especially in specialized electric lamps (as flashtubes) and in scientific research — see element table