Chickadees are any of several crestless American songbirds usually having the crown of the head sharply demarked and darker than the body plumage.
The tits, chickadees, and titmice constitute Paridae, a large family of small passerine birds which occur in the northern hemisphere and Africa. Most were formerly classified in the genus Parus. These birds are called either 'chickadees' (onomatopoeic, derived from their distinctive 'chick-a dee dee dee' alarm call) or 'titmice' in North America, and just 'tits' in the rest of the English-speaking world. The name titmouse is recorded from the 14th century, composed of the Old English name for the bird, mase (Proto-Germanic *maison, German Meise) and tit, denoting something small. The spelling was influenced by mouse in the 16th century. Emigrants to New Zealand presumably identified some of the superficially similar birds of the genus Petroica of the family Petroicidae, the Australian robins, as members of the tit family, giving them the title Tomtit although, in fact, they are not related.
Contributions by Jimfbleak, Sabine's Sunbird, and ClueBot.