The term 'grandparent' is used for both male and female genders. The male grandparent is called a grandfather. The female grandparent is a grandmother. When looking at the relationship from the point of view of the grandparent, the term grandchild is used. A grandchild is the child of a person's child. It can also be used based on gender. Grandchild is correct for either gender. Grandson is male. Granddaughter is female.