10 October 2009
Xenon, element 54, was discovered in 1898 by British chemists William Ramsay and Morris Travers. The pair had discovered krypton and neon a short time before. Their choice of a name comes from the Greek ξένος (xenos), meaning stranger or foreigner, presumably because the gas is so rare in the earth’s atmosphere. Ramsay and Travers wrote in the Report of the British Association for the Advancement of Science that year:
The last fractions of liquefied argon show the presence of three new gases. These are krypton [...] metargon [...] and a still heavier gas, [...] which we propose to name “xenon.”
Xenon has the chemical symbol Xe.
Oxford English Dictionary, xenon, 2nd Edition, 1989