御中[onaka] stomach
御話中[ohanashichuu] busy (phone)
アル中[aruchuu] alcoholism
π中間子[paichuukanshi] pi meson
暗中[anchuu] in the dark

暗中摸索[anchuumosaku] groping in the dark
意中[ichuu] one's mind
意中の女[ichuunoonna] sweetheart
井の中の蛙大海を知らず[inonakanokawazutaikaiwoshirazu] parochial
一日中[ichinichijuu] all day long

ない交ぜにする[naimazenisuru] to blend (e.g. truth and lies)
データ交換[deetakoukan] data exchange
メール交換[meerukoukan] exchange of letters
リーダー交代[riidaakoutai] leadership change
意見交換[ikenkoukan] exchange of ideas

一方交通[ippoukoutsuu] one-way traffic
羽交絞め[hagaijime] pinioning
仮名交じり[kanamajiri] mixed writing (characters and kana)
仮名交じり文[kanamajiribun] mixed writing (characters and kana)
賀詞交換[gashikoukan] New Year greetings (parties)

アナログデジタル変換器[anarogudejitaruhenkanki] analog-digital converter
データ交換[deetakoukan] data exchange
パリティ変換[paritihenkan] parity transformation (physics)
メール交換[meerukoukan] exchange of letters
意見交換[ikenkoukan] exchange of ideas

引換て[hikikaete] on the contrary
下位互換性[kaigokansei] downward compatibility
かな漢字変換[kanakanjihenkan] kana-kanji conversion (on a computer, etc.)
可換群[kakangun] Abelian group
賀詞交換[gashikoukan] New Year greetings (parties)

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

一重継ぎ[hitoetsugi] sheep bend (knot)
引継ぐ[hikitsugu] to take over
継合せる[tsugiawaseru] to join together
継接ぎ[tsugihagi] patching (and darning)
継足す[tsugitasu] to extend (e.g. a house)

継ぐ[tsugu] to succeed (someone in a business or inheritance)
継嗣[keishi] successor
継っ子[keishi] stepchild
継承[keishou] inheritance
継承者[keishousha] successor