The chickadees are a group of North American birds in the family Paridae included in the genus Poecile. Species found in North America are referred to as chickadees; species found elsewhere in the world are called tits. They are small-sized birds overall, usually having the crown of the head and throat patch distinctly darker than the body. They are at least 6 to 14 centimeters in size.

Poecile is a genus of birds in the tit family Paridae. It contains 15 species, which are scattered across North America, Europe and Asia; the North American species are the chickadees. In the past, most authorities retained Poecile as a subgenus within the genus Parus, but treatment as a distinct genus, initiated by the American Ornithologists Union, is now widely accepted. This is supported by mtDNA cytochrome b sequence analysis.