interlock

/IH0 N T ER0 L AA1 K/
noun
  1. 1

    A safety device that prevents activation in unsafe conditions.

    โ€œThe demonstrator couldn't figure out why the machine wouldn't work, until he remembered that there was an interlock so it wouldn't operate with the cover open.โ€

verb
  1. 1

    To fit or clasp together securely.

  2. 2

    To interlace.

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