warble

Meanings

1. To modulate a tone's frequency.
2. To sing like a bird, especially with trills.
3. To cause to quaver or vibrate.
4. To be quavered or modulated; to be uttered melodiously.

1. The sound of one who warbles; singing with trills or modulations.
2. In naval mine warfare, the process of varying the frequency of sound produced by a narrowband noisemaker to ensure that the frequency to which the mine will respond is covered.

1. A lesion under the skin of cattle, caused by the larva of a bot fly of genus Hypoderma.
2. A small hard swelling on a horse's back, caused by the galling of the saddle.

Etymology

Perhaps onomatopoeic.