atomic number 54

Definitions of atomic number 54

n a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts

Xe, xenon
Type of:
chemical element, element
any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
argonon, inert gas, noble gas
any of the chemically inert gaseous elements of the helium group in the periodic table