kryp ‧ ton /ˈkrɪptɒn $ -tɑːn/ BrE AmE noun [uncountable]
[ Date: 1800-1900 ; Language: Greek ; Origin: kryptos 'hidden' ]
a colourless gas that is found in very small quantities in the air and is used in ↑ fluorescent lights and ↑ laser s . It is a chemical ↑ element : symbol Kr.