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

委任[inin] charge
委任状[ininjou] commission
一任[ichinin] entrusting
引責辞任[insekijinin] taking responsibility upon oneself (and resigning)
解任[kainin] dismissal

帰任[kinin] return to one's post
共同責任[kyoudousekinin] joint responsibility
兼任[kennin] concurrent post
後任[kounin] successor
口任せ[kuchimakase] random talk