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.
Osteopenia is defined as low bone density caused by bone loss. Osteopenia is often a precursor to osteoporosis, a common condition of brittle bones that can result in fracture. The two medical terms are sometimes confused and it's important to know the difference and how each is related to arthritis.