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

一叢[hitomura] copse
稲叢[inamura] stack of rice straw
叢がる[muragaru] to swarm
叢雨[murasame] passing shower
叢時雨[murashigure] autumn shower

叢書[sousho] series (of publications)
叢生[sousei] dense growth
叢談[soudan] collection of stories
叢氷[souhyou] pack ice
叢立ち[soudachi] standing in a group