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

に過ぎない[nisuginai] no more than
マルコフ過程[marukofukatei] Markov process
為過ぎる[shisugiru] to overdo
一過[ikka] passing away
一過性[ikkasei] transient (pain or fever)

過ぎ[sugi] past
過ぎる[sugiru] to pass through
過ぎ去った可能性[sugisattakanousei] might-have-been
過去る[sugisaru] to pass
過す[sugosu] to pass (time)