stratum; strata(plural)

• 社会的个别阶层

  individual social strata

• 各阶层人民

  people from all social strata

• 特权阶层

  privileged class

• 高薪阶层

  high-salaried class

• 工薪阶层

  wage-earning class

• 知识分子阶层

  intellectual class