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

一臂[ippi] (a) (helping) hand
三面六臂[sanmenroppi] rush of business
八面六臂[hachimenroppi] competent in all fields
猿臂[enpi] long, protruding elbows (like those of a monkey)

猿臂を伸ばす[enpiwonobasu] to stretch one's arms
半臂[hanpi] short-sleeved (or sleeveless) undergarment worn by aristocratic men
半臂の緒[hanpinoo] decorative gauze strap that hangs from the front left side of the kohimo when tying closed one's hanpi
猿臂打ち[enpiuchi] elbow strike (karate)