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

一区[ikku] district
街区[gaiku] block (of land)
学区[gakku] school district
管区[kanku] jurisdiction
共産地区[kyousanchiku] communist area

教区[kyouku] parish
区域[kuiki] limits
区会[kukai] ward assembly
区会議員[kukaigiin] ward assemblyman