Jodan Tettsui Yoko Uchi is a technique in Kyokushin karate. It translates to 'High-Level Hammer Fist Side Strike.' This technique involves delivering a powerful strike with the hammer fist to the opponent's side at a high level. The term 'Jodan' refers to the high level, 'Tettsui' indicates the hammer fist, and 'Yoko Uchi' refers to the side strike. It is commonly used to target the ribs or floating ribs with significant force.