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

一閃[issen] flash
閃かす[hiramekasu] to brandish
閃き[hirameki] flair
閃く[hirameku] to flash (lightning, etc.)
閃光[senkou] flash

閃光電球[senkoudenkyuu] flash bulb
花崗閃緑岩[kakousenryokugan] granodiorite
紫電一閃[shidenissen] flash of lightning
電光一閃[denkouissen] flash of lightning
閃緑岩[senryokugan] diorite (a type of rock similar to granite)