Metta World Peace -- Picks NBA Finals Winner ... Loses Spelling Bee

Lakers star Metta World Peace went out on a limb -- making a bold prediction on who will win the NBA Finals ... and then the limb snapped when he tried to spell his pick.

We'll tell you this much ... Metta's riding with the San Antonio Spurs to take down LeBron James and the Miami Heat -- but you gotta hear how he spells it.

He might have been joking, but then again ...