n.
Pronunciation: ' h ē -l ē - ə m, ' h ē l-y ə m
Function: noun
Etymology: New Latin, from Greek h ē lios
Date: 1872
: a light colorless inert gaseous element found especially in natural gases and used chiefly for inflating airships and balloons, in lamps, in cryogenic research, and as a component of inert atmospheres (as in welding) ― see ELEMENT table