WARBLE
warble
Noun
- In naval mine warfare, the process of varying the frequency of sound produced by a narrow band noisemaker to ensure that the frequency to which the mine will respond is covered.
Noun (etymology 2)
Verb
- to modulate a tone's frequency
- to sing like a bird, especially with trills.
- To cause to quaver or vibrate.
- To be quavered or modulated; to be uttered melodiously.
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