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.^[1][2] 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 (2.4 to 5.5 inches) in size.

Their name reputedly comes from the fact that their calls make a distinctive “chick-a-dee-dee-dee”,^[3] though their normal call is actually “fee-bee,” and the “chick-a-dee-dee-dee” call is an alarm call. The number of “dees” depends on the predator.^[4]

The chickadee (specifically the black-capped chickadee Poecile atricapillus, formerly Parus atricapillus) is the official bird for the US states of Massachusetts and Maine,^[5][6][7] the Canadian province of New Brunswick,^[8] and the city of Calgary, Alberta.^[9]

One holarctic species is referred to by a different name in each part of its range: grey-headed chickadee in North America and Siberian tit in Eurasia.