shutoff

/SH AH1 T AO0 F/
noun
  1. 1

    A valve used to turn off something.

    โ€œThe fire raged for hours because they were unable to reach the shutoff for the gas line.โ€

  2. 2

    The act of turning off something.

    โ€œThe letter warned of an impending shutoff if payment was not made promptly.โ€

Source: https://en.wiktionary.org/wiki/shutoff