In a person with cleft lip, the two sides of the upper lip do not meet in the center, leaving a gap.

In a person with a cleft palate, the two sides of the roof of the mouth do not meet in the center, leaving a gap in the roof of the mouth.

Cleft lip and cleft palate are conditions that occur during fetal development and are present at birth. Cleft lip and cleft palate can occur on just one side of the palate, or they may occur on both sides. Each condition can occur alone, without the other.