Please describe the medical term for a cleft palate?

Coloboma: I've not heard "cleft" being used in reference to the eye, but when used in reference to the lip or palate, for instance, it refers to incomplete developmental closure of the tissue. In the eye, that is called coloboma. There are different degrees from iris only to involvement of the retina and optic nerve. The latter can be associated with severe vision deficit.

Hole in top of mouth: Cleft palate is a hole in the roof of the mouth that some babies are born with. It always involves the back of the palate by the uvula, and can extend forward a little bit, or all the way through the gum line.