A dog whistle is a type of whistle used in the training of dogs. The frequency range of a dog whistle is largely out of the range of human hearing. Typically, a dog whistle is within the range of 5800 Hz to 12400 Hz (disputed — see talk page). more...
Some dog whistles have adjustable sliders for active control of the frequency produced.
Depending on the way the whistle is used, a trainer may simply gather a dog's attention or inflict pain for the purpose of behavior modification.
The name dog whistle is often used for both lung-powered whistles as well as electronic devices that emit ultrasonic sound via piezoelectric emitters. The electronic variety are sometimes coupled with bark detection circuits in an effort to curb barking behavior.
Some political observers have used the phrase "dog whistle politics" to refer to the use of words and phrases that one's political allies will recognize and appreciate but that may not mean anything to other listeners. For example, members of the United States' Republican Party sometimes speak of a "culture of life", which sounds innocuous but is typically interpreted by political allies as a reaffirmation of the speaker's opposition to abortion rights. So, the idea is that one uses words and phrases that only one's political allies will hear and recognize.
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