The terms
cleft chin,
chin cleft,
dimple chin, or
chin dimple, refer to a
dimple on the
chin. It is a
Y-shaped fissure on the chin with an underlying bony peculiarity. Specifically, the chin fissure follows the fissure in the lower
jaw bone that resulted from the incomplete fusion of the left and right halves of the jaw bone, or muscle, during the embryonal and fetal development. For other individuals, it can develop over time, often because one half of the jaw is longer than the other, leading to facial asymmetry.