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

お風呂に入る[ofuronihairu] to take a bath
鍬入れ式[kuwaireshiki] ground-breaking ceremony
塵入[gomiire] trashcan
キー入力[kiinyuuryoku] key (input)
ビジネススクール入学共通試験[bijinesusukuurunyuugakukyoutsuushiken] business school entrance test

メスを入れる[mesuwoireru] to operate
圧入[atsunyuu] indentation
移入[inyuu] importation
一寝入り[hitoneiri] nap
一入[hitoshio] still more