Incest refers to a deviant sexual attraction (pedophilia) directed toward a family member; most often the attraction of a father toward a daughter who is maturing physically, also bro ther and sister.

Likewise, Incest is a sexual activity between individuals so closely related that marriage is prohibited; sexual contact or relations between persons who are related or have a caregiving relationship.

Incest involving a child is a form of child abuse.
Other /More definition:
Incest refers to deviant sexual attraction (pedophilia) directed toward a family member; most usually the attraction of a father toward a daughter who is maturing physically. Moreover, it is the sexual activity between individuals so closely related that marriage is prohibited. Incest involving a child is a form of child abuse.