石炭系

shítànxì
  1. carboniferous system
  2. coal measure (geology)

CEDICT

geology

Entry Composition

1 石炭 shítàn coal (old)
=2 系 xì
  1. to connect
  2. to relate to
  3. to tie up
  4. to bind
  5. to be (literary)
=2 系 xì
  1. system
  2. department
  3. faculty
=2 系 xì
  1. to connect
  2. to arrest
  3. to worry