left-handed outside grip on the opponent's belt
Sumo-specific term. Refers to gripping the opponent's belt (mawashi) from the outside with the left hand, often used to control or throw.
He got a left-handed outside grip and forced his opponent out.
Compound of 左 (hidari, 'left') and 上手 (uwate, 'overarm grip' or 'upper hand'). The reading うわて is standard for this sumo usage.