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

御寝小[onesho] bed-wetting
小便をする[shoubenwosuru] to pee
悪戯小僧[itazurakozou] mischievous boy
右小括弧[migishoukakko] closing parenthesis
永小作[eikosaku] perpetual land lease

英小文字[eikomoji] lower-case letters
仮小屋[karigoya] booth
過小[kashou] too small
過小評価[kashouhyouka] underestimation
甘い小説[amaishousetsu] sentimental novel

何時もより[itsumoyori] more than usual
御三時[osanji] three-o'clock snack
ある時[arutoki] once (i.e. "once, when I was studying ..")
安静時[anseiji] resting
安土桃山時代[azuchimomoyamajidai] Azuchi-Momoyama period (approx. 1558-1600 CE)

暗黒時代[ankokujidai] Dark Ages
育児時間[ikujijikan] nursing time
ひと時[ittoki] moment
一時に[ichidokini] at the same time
一時間[ichijikan] one hour

あっとゆう間に[attoiumani] just like that
此間[konaida] the other day
此の間[konokan] the other day
間誤付かせる[magotsukaseru] to fluster
間誤付く[magotsuku] to be confused

クローン人間[kuroonningen] (human) clone
シゾイド人間[shizoidoningen] schizoid person
ベクトル空間[bekutorukuukan] vector space
π中間子[paichuukanshi] pi meson
位相空間[isoukuukan] phase space (physics)