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

一徹[ittetsu] obstinate
一徹者[ittetsumono] stubborn person
貫徹[kantetsu] accomplishment
周知徹底[shuuchitettei] (something) known to all
初志貫徹[shoshikantetsu] carrying out one's original intention

徹す[toosu] to stick through
徹る[tooru] to go by
徹甲弾[tekkoudan] armor piercing ammunition
徹宵[tesshou] all night
徹底[tettei] thoroughness

老麺[raamen] ramen (Chinese-style noodles)
家老[karou] chief retainer
棄老[kirou] old person thrown away in the mountains
敬老[keirou] respect for the aged
敬老の日[keirounohi] Respect-for-the-Aged Day Holiday (third Monday in September)

元老[genrou] elder statesman
元老院[genrouin] (Roman) senate
故老[korou] old people
車海老[kurumaebi] kuruma prawn (Marsupenaeus japonicus)
寿老人[juroujin] god of longevity