Seiken Chudan Uchi Uke Gedan Barai is a combination technique in Kyokushin karate. It involves simultaneously performing a middle-level inward block with the forefist and a downward block with the forearm. The term 'Seiken' refers to the forefist, 'Chudan' indicates middle level, 'Uchi Uke' means inward block, and 'Gedan Barai' refers to the downward block. This technique is used to defend against lower-level strikes while also protecting the midsection.