Containing, or like, chalk chalky.

【地】含白垩的；似白垩的；白垩的。

Of, relating to, or being the last period of the Mesozoic era characterized by continued dominance of reptiles, emergent dominance of angiosperms, diversification of mammals, and the extinction of many types of organisms at the close of the period.

【地】白垩纪。中生代(Mesozoic)的第三纪(最后一纪)，距今约一亿四千万─六千五百万年前。