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

御世辞[oseji] flattery
御世話になる[osewaninaru] to receive favor (favour)
一世紀[isseiki] century
永世[eisei] eternity
永世中立[eiseichuuritsu] permanent neutrality

永世中立国[eiseichuuritsukoku] permanent neutral country
厭世[ensei] pessimism
厭世家[enseika] pessimist
厭世観[enseikan] pessimistic view of life
厭世主義[enseishugi] pessimism

一元[ichigen] unitary
一元化[ichigenka] unification
一元的[ichigenteki] monistic
一元論[ichigenron] monism
一次元[ichijigen] one dimensional

一新紀元[isshinkigen] new era
隠元[ingen] beans
隠元豆[ingenmame] common bean (Phaseolus vulgaris)
家元[iemoto] head of a school (of music, dance)
火の元[hinomoto] origin of fire