One who has reached an expertise level with his frag grenades from the video game series Call of Duty.
A true frag master has the ability to cook their frags, throw them over a building, bounce it off of an enemy in last stand, kill them direct impact, and have the blast explode in a minimum of but not limited to three enemies faces rendering them all incomparable of remembering why the even bought the game.
*Player killer by grenade and watches killcam

Player: AWW WTF!?! That nade bounced off 3 different people in last stand then fell and killed me!!!

Killer: I am the Frag Master!
by TreeBobJoe December 13, 2010
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