第四紀 [ㄉㄧˋ ㄙˋ ㄐㄧˋ; di4 si4 ji4] fourth period quaternary (geological period covering the recent ice ages over the last 180,000 years) ◄ ►
第四紀 だいよんき だいしき noun (common) (futsuumeishi) Quaternary period ◄ ►