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

一隊[ittai] party
掩護部隊[engobutai] covering force
横隊[outai] rank
火力支援部隊[karyokushienbutai] fire support element
海兵隊[kaiheitai] Marine Corps

外国部隊[gaikokubutai] overseas (military forces)
格闘戦部隊[kakutousenbutai] shock troops
楽隊[gakutai] band
艦隊[kantai] (naval) fleet
機動隊[kidoutai] riot police