n. Symbol Kr A colorless, largely inert gaseous element used chiefly in gas discharge lamps and fluorescent lamps. Atomic number 36; atomic weight 83.80; melting point -157.36°C; boiling point -153.34°C; density 3.733 grams per liter (0°C). See Periodic Table. [Greek krupton, neuter of kruptos, hidden (from its rarity), from kruptein, to hide.] |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.