interlock

English

Etymology

inter- +‎ lock

Verb

interlock (third-person singular simple present interlocks, present participle interlocking, simple past and past participle interlocked)

1. To fit together securely.
2. To interlace.

Noun

interlock (plural interlocks)

1. A safety device that prevents activation in unsafe conditions.

   The 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.