A small brown European songbird (Prunella modularis) with a gray head, also called a hedge sparrow.
From Middle English 'donne' (dun-colored) plus the diminutive suffix '-ock'. The bird was named for its dull brown plumage. The term has been used in English ornithology since at least the 16th century.
The dunnock is secretly one of the most fascinating garden birds—despite their mouse-like, shy appearance, they have a surprisingly complex mating system where multiple males will mate with multiple females in the same territory, and the males even perform a bizarre 'sperm competition' behavior by pecking the female's cloaca before mating.
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