Homicide and suicide apply to individuals. Genocide applies to a group. You don't have to kill every living member of a group to eliminate it. For example, you

Homicide and suicide apply to individuals. Genocide applies to a group. You don't have to kill every living member of a group to eliminate it. For example, you could just sterilize the females. Which is why that practice (along with kidnapping/relocating children) is recognized as such.