Seiken Shita Uchi is a technique in Kyokushin karate. It involves striking downward with the fist. The term 'Seiken' refers to the forefist or the first two knuckles of the fist. 'Shita' means 'down,' and 'Uchi' means 'strike.' This technique is typically aimed at targets such as the solar plexus, groin, or thighs.