What are examples of landforms? A: The four main types of landforms are mountains, plateaus, plains and hills. A landform is defined as any natural feature on the Earth's surface, which incl... Full Answer >
Definition of leukopenia. : a condition in which the number of white blood cells circulating in the blood is abnormally low.
Leukopenia, or a low white blood cell count, is the condition of having a decreased level of disease-fighting cells in your blood. But what causes low white cells in the blood?