Transducer that converts the energy supplied or taken from the surroundings into some mechanical motion.
Note:
Human muscles, motors, loudspeakers and various piezoelectric devices are examples of actuators.
Source:
PAC, 2022, 94, 15. 'Glossary of terms relating to electronic, photonic and magnetic properties of polymers (IUPAC Recommendations 2021)' on page 17 (https://doi.org/10.1515/pac-2020-0501)