warble

Warble is a term with several related meanings in music, ornithology, and animal health. As a verb, to warble means to sing or speak with a quavering, vibrato-like quality, often with rapid fluctuations in pitch. It can also describe ornamenting a melody with a rapid, varied sequence of notes. As a noun, a warble is the sound produced by warbling—a tremulous, lilting song or trill, especially by birds. In ornithology, many songbirds are described as warbling; the terms warble and warbler are etymologically linked and appear in discussions of bird vocalizations.

In biology and agriculture, warble refers to a parasitic condition caused by certain fly larvae, known as warble flies. Adult flies lay eggs on the coats of cattle and horses; the hatched larvae burrow through the skin and migrate to the back, where they form subcutaneous nodules or “warbles.” The condition can cause irritation, reduced weight gain, and hide damage. Diagnosis is by observation of lumps and larval debris; prevention and treatment involve management strategies and anthelmintic controls.

In musical usage, warble describes a decorative vocal or instrumental effect—rapid, alternating pitches or a tremolo-like figure used to enrich a melodic line.

The term is widely associated with the concept of a warbler, a small bird notable for its singing. See also: warbler, trill.