御構いなく[okamainaku] please don't fuss over me
サーボ機構[saabokikou] servomechanism
シフト演算機構[shifutoenzankikou] shift arithmetic unit
ヒグス機構[higusukikou] Higgs mechanism (physics)
遺構[ikou] remains

一向に構わない[ikkounikamawanai] doesn't care at all
一般命令演算機構[ippanmeireienzankikou] general instruction unit (computer)
機構[kikou] mechanism
気構え[kigamae] readiness
虚構[kyokou] fiction

鬥構え[tougamae] kanji "fighting" radical