actuator

Meanings

1. Something that actuates something else.
2. A usually electric device that causes a mechanical device (i.e., a mechanism) to be switched on or off. For example; an electric motor that opens and closes a valve.
3. The mechanism that moves the head assembly on a disk drive.
4. A relay that controls the flow of electricity.

Etymology

Etymology tree Proto-Indo-European *h₂eǵ- Proto-Indo-European *-eti Proto-Indo-European *h₂éǵeti Proto-Italic *agō Latin agō Proto-Indo-European *-tus Proto-Italic *-tus Latin -tus Latin āctus Proto-Indo-European *-h₂ Proto-Indo-European *-éh₂ Proto-Indo-European *-yéti Proto-Indo-European *-eh₂yéti Proto-Italic *-āō Latin -ō Latin āctuō Medieval Latin āctuātusder. English actuate Proto-Indo-European *-tōr Proto-Italic *-tōr Latin -tor Latin -ātor Old French -eorbor. Middle English -our ▲ Latin -torlbor. English -or English actuator From actuate + -or. First attested in 1652.