/ Dictionary / Index A actuator: Meaning and Definition of Find definitions for: ac•tu•a•tor Pronunciation: (ak'ch-ā"tur), [key] — n. a person or thing that actuates. a servomechanism that supplies and transmits a measured amount of energy for the operation of another mechanism or system. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: actuator (Thesaurus) actuate act warning Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language