radon
noun
- chemical element with the atomic number of 86
Wiktionary
Pronunciation: /ˈɹeɪdɒn/
name
- A surname from German.
- A surname from German.
noun
Etymology: Contraction of radium emanation, since the element appears in the radioactive decay of radium. By surface analysis, radio- + -on (“suffix for noble gases”).
- The chemical element (symbol Rn, formerly Ro) with atomic number 86. It is an odorless, colorless, chemically inert but radioactive noble gas.
- Radon-222 (22286Rn), the most stable isotope of said element.