n 1  :  a soft silver-white element of the alkali metal group that is the lightest metal known and that is used in chemical synthesis and in storage batteries - symbol Li - see ELEMENTtable    2  :  a lithium salt and esp. lithium carbonate used in psychiatric medicine .
 
 
 
Similar sounding terms:  li·the·mia 
 
Published under license with Merriam-Webster, Incorporated.  © 1997-2004.