孩子气

孩子气:

Literally means:

childish; being naive.

Actually means:

It figuratively means an adult has a childlike character, temperament, expression or appearance.

It also figuratively means an adult is naive or unintelligent like a child.

In the latter case, it is derogatory.

孩子气，形容成年人具有像孩子一样的性格、脾气、神情或外表。

它也形容成年人像孩子一样天真幼稚或不懂事。后者具有贬义色彩。