底層

底层
dǐcéng
  1. ground floor; first floor
  2. lowest level; lowest rung (of society etc)

CEDICT

Entry Composition

1 底 dǐ
  1. bottom; base
  2. background; foundation
  3. copy (of a manuscript or receipt etc) kept as a record
  4. (suffix) end of a year or month
  5. (math.) radix; base (abbr. for 底數 dǐshù)
2 層 céng
  1. to pile on top of one another
  2. layer; stratum
  3. floor (of a building); story
  4. (math.) sheaf
  5. classifier for layers