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

異常終了[ijoushuuryou] abnormal termination (e.g. of a program)
一了簡[ichiryoukan] at one's discretion
完了[kanryou] completion
ご了承[goryoushou] acknowledgement
校了[kouryou] proofreading completed

三校終了[sankoushuuryou] third and final proof
了う[shimau] to finish
修了[shuuryou] completion (of a course)
修了証書[shuuryoushousho] diploma
了える[oeru] to finish

いとも簡単に[itomokantanni] very easily
一了簡[ichiryoukan] at one's discretion
簡易[kani] simplicity
簡易化[kanika] simplification
簡潔[kanketsu] brevity

簡素[kanso] simplicity
簡素化[kansoka] simplification
簡体字[kantaiji] simplified Chinese character
簡短[kantan] simple
簡単に言うと[kantanniiuto] simply put