"Frag", meaning to kill a fellow soldier, started as a short form of this term for a type of grenade
The American Heritage 
Dictionary of the ... Computer Desktop Encyclopedia THIS DEFINITION IS FOR 
PERSONAL... [DOC] [TLE] Fragging | Define Fragging at Dictionary.com [PAR] Fragging definition, to kill, wound, or assault (especially an unpopular or 
overzealous superior) with a fragmentation grenade.