1. Noun

   deadline; closing; cut-off

   also written as 〆切(り)

   レポートの締め切りが間近に迫っているので、私はひどく忙しい。

2. closing (a door, window, etc.)

   also written as 閉め切り

3. cofferdam

Also written 締切【しめきり】shimekiri、締切り【しめきり】shimekiri