What does it mean when someone requests a right handed baseball glove?

A baseball glove or mitt is described by the handedness of the intended wearer, rather than the hand on which the glove is worn: a glove that fits on the left hand—used by a right-handed thrower—is called a right-handed (RH) or "right-hand throw" (RHT) glove. Conversely, a left-handed glove (LH or LHT) is worn on the right hand, allowing the player to throw the ball with the left hand.