We don't have synonyms for noble gases yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are noble gas.
(n) :
(chemistry) Any of the elements of group 18 of the periodic table, being monatomic, usually inert (with very limited exceptions), and gaseous at familiar temperatures.
(n) :
(chemistry) Any of the elements of group 18 of the periodic table, being monatomic, usually inert (with very limited exceptions), and gaseous at familiar temperatures.