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

モーメント項[moomentokou] momentum
移項[ikou] transposition
一項[ikkou] an item
会議事項[kaigijikou] agenda

関連項目[kanrenkoumoku] related item
協議事項[kyougijikou] agenda
項書換え[koukakikae] term rewriting
項目[koumoku] (data) item