Produces sonic oscillations or alternating current.
An electronic circuit that produces a periodically varying output at a controlled frequency. Oscillators, an important type of electronic circuit, can be designed to provide a constant or an adjustable output. Some oscillator circuits use a quartz crystal to generate a stable frequency. Personal computers use an oscillator circuit to provide the clock frequency—typically 1 to 200 megahertz (MHz)—that drives the processor and other circuits.

Any device producing a desired oscillation (vibration). There are many types of oscillator for different purposes, involving various arrangements of thermionic valves or components such as transistors, inductors, capacitors, and resistors.
An oscillator is an essential part of a radio transmitter, generating the high-frequency carrier signal necessary for radio communication. The frequency is often controlled by the vibrations set up in a crystal (such as quartz).

In music, an electrical generator used to convert electricity into sound. It produces an oscillating current that may be heard as sound when played at a frequency between 16 Hz and 20,000 Hz and attached to an amplifier and loudspeakers. Different types of tones produced by an oscillator include sine waves and saw-toothed waves.