悔改める[kuiaratameru] to repent
改まる[aratamaru] to be renewed
改めて[aratamete] another time
改める[aratameru] to change
改悪[kaiaku] deterioration

改印[kaiin] changing seals
改革[kaikaku] reform
改革案[kaikakuan] reform proposal
改革過程[kaikakukatei] reform process
改憲[kaiken] constitutional change

機関[karakuri] mechanism
アナログ計算機[anarogukeisanki] analog computer
エンジン発動機[enjinhatsudouki] engine
サーボ機構[saabokikou] servomechanism
シフト演算機構[shifutoenzankikou] shift arithmetic unit

ジェット機[jettoki] jet aeroplane
弾機[hatsujou] spring (e.g. coil, leaf)
ヒグス機構[higusukikou] Higgs mechanism (physics)
プロペラ機[puroperaki] propeller-driven aircraft
圧延機[atsuenki] rolling machine