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

ひと塊[ikkai] one lump
塊根[kaikon] tuberous root
塊状[kaijou] massive
凝塊[gyoukai] clot
金塊[kinkai] nugget

集塊[shuukai] agglomerate (e.g. of cells, molecules, etc.)
団塊の世代[dankainosedai] baby boom generation
土塊[dokai] lump of earth
肉塊[nikukai] piece of meat
氷塊[hyoukai] lump of ice