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

一俵[ippyou] one (straw) bagful
炭俵[sumidawara] sack for charcoal
土俵[dohyou] arena, esp. in sumo
俵数[hyousuu] number of straw bags
俵物[tawaramono] goods in straw bags

米俵[komedawara] bag of rice
土俵入り[dohyouiri] entrance procession of sumo wrestlers into the ring
土俵際[dohyougiwa] edge of the ring
桟俵[sandawara] straw lid covering either end of a rice container