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

一呑み[hitonomi] swallowing in one gulp
呑口[nomikuchi] taste (of a liquid, esp. alcoholic beverages)
呑み代[nomishiro] drink money
呑む[nomu] to drink
呑み助[nomisuke] tippler

鵜呑み[unomi] swallowing (food, story)
雲呑[wantan] wonton (Chinese dumpling)
丸呑み[marunomi] swallowing whole
険呑[kennon] risky
固唾を呑む[katazuwonomu] to hold one's breath (in fear, anxiety, etc.)