Something that is timeless does not change as the years go past.

The city has a timeless quality as if it had existed forever. 该市具有一种永恒的品质，似乎它亘古以来就存在。

having a value that is not limited to a particular period but will last for ever

a timeless book/play/film/classic 一部流传百世的书／戏剧／电影／经典作品

timeless values/questions 永恒的价值／问题

Rothko's paintings have a timeless quality. 罗思科的绘画作品具有一种超越时光的品质。