|1.||an electronic device used to increase the strength of the signal fed into it|
|2.||such a device used for the amplification of audio frequency signals in a radio, etc|
|3.||photog an additional lens for altering the focal length of a camera lens|
|4.||a person or thing that amplifies|
In electronics, a device that takes a small electric signal and converts it into a large one. Amplifiers are used in stereo systems, electric guitars, and loudspeakers.