[] a level or part within a system or set of ideas层次；阶层◆There were too many layers of management in the company.这家公司的管理层有太多层级。 a quantity or thickness of sth that lies over a surface or between surfaces层；表层◆Finally, three layers of protective coating are sprayed onto the wood.最后，在木材上喷上三层防护涂层。