古往今来[kooukonrai] in all ages
古今[kokon] ancient and modern times
古今東西[kokontouzai] all times and places
古今無類[kokonmurui] best ever

今か今か[imakaimaka] eagerly waiting
今が今[imagaima] just now
今が今まで[imagaimamade] till just now
今しがた[imashigata] moment ago

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