[hair-lip] 
| 1. | a congenitally deformed lip, usually the upper one, in which there is a vertical fissure causing it to resemble the cleft lip of a hare. |
| 2. | the deformity itself. |
| cleft lip n. A congenital deformity characterized by a vertical cleft or pair of clefts in the upper lip, with or without involvement of the palate. |
A congenital defect in which the upper lip is not properly fused together, so that a narrow crack or fissure splits the lip. It can be repaired through plastic surgery.
cleft lip n.
A congenital facial deformity of the lip, usually the upper lip, due to a mesodermal deficiency or to a failure of merging in one or more of the embryologic processes that form the lip; it is frequently associated with cleft tooth socket and cleft palate. Also called cheiloschisis, harelip.
harelip hare·lip (hâr'lĭp')
n.
See cleft lip.
| cleft lip (klěft) Pronunciation Key
A congenital deformity characterized by a vertical cleft or pair of clefts in the upper lip, with or without involvement of the palate. |
cleft lip
relatively common (one out of every 1,000 births) congenital deformity in which the central to medial lip fails to fuse properly during the first month of prenatal life, resulting in a fissure in the lip beneath the nostril. Once colloquially known as harelip, cleft lip may be unilateral or bilateral, it may take the form of anything from a small pit to a complete fissure the height of the lip, and it may occur alone or in conjunction with cleft palate (a fissure in the roof of the mouth). The deformity is sometimes familial; animal experiments suggest it may also occur following some abnormality of intrauterine environment. It is a frequent finding in certain chromosomal disorders. Surgery to repair the defect is performed in the first two months of life and is usually successful.
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