noun Date: 1902 any of a group of rare gases that include helium, neon, argon, krypton, xenon, and usually radon and that exhibit great stability and extremely low reaction rates
NOBLE GAS
Meaning of NOBLE GAS in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012