ちょっと一杯[chottoippai] let's have a quick drink
ばつ一[batsuichi] being once divorced
一向[hitaburu] nothing but
サラダ一皿[saradahitosara] plate of salad

安全第一[anzendaiichi] safety first
一か八か[ichikabachika] sink or swim
一っ走り[hitoppashiri] spin (as in 'take a car for a spin')
一つ一つ[hitotsuhitotsu] one-by-one

安危[anki] fate
危うい[ayaui] dangerous
危うく[ayauku] barely
危ない[abunai] dangerous
危ながる[abunagaru] to be afraid of

危なっかしい[abunakkashii] dangerous
危ぶむ[ayabumu] to fear
危める[ayameru] to wound
危絵[abunae] suggestive or indecent picture
危害[kigai] injury

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

遺髪[ihatsu] hair of the deceased
一髪[ippatsu] hair
下げ髪[sagegami] pigtail
間一髪[kanippatsu] hair's breadth
間一髪のところ[kanippatsunotokoro] close call

間一髪を入れず[kanippatsuwoirezu] in a flash
危機一髪[kikiippatsu] by a hair's breadth
共白髪[tomoshiraga] growing old together (a couple)
襟髪[erigami] scruff of neck
金髪[kinpatsu] blond hair