Hidden facts, feelings, activities, or problems are not easy to notice or discover.
Under all the innocent fun, there are hidden dangers, especially for children.
在所有无害的娱乐节目背后都有隐患,对儿童来说尤其如此。
A hidden place is difficult to find.
As you descend, suddenly you see at last the hidden waterfall.
你往下走,最终会突然发现那个隐秘的瀑布。
Hidden is the past participle of hide.