n.
Pronunciation: ' li-th ē - ə m
Function: noun
Etymology: New Latin, from lithia oxide of lithium, from Greek lithos
Date: 1818
1 : a soft silver-white element of the alkali metal group that is the lightest metal known and that is used especially in alloys and glass, in chemical synthesis, and in storage batteries ― see ELEMENT table
2 : a salt of lithium (as lithium carbonate) used in psychiatric medicine