What is the medical term meaning contagious condition?

A contagious disease is a disease that can be transmitted from an infected person to another. Not all contagious diseases require direct physical contact. For instance, a mosquito can bite an infected person who has malaria and then later bite a person who does not have malaria, and they can contract malaria without ever seeing the other infected person. Some diseases are called 'air borne' which means the disease travels through the air from one person to another.

Sometimes just being in the same room where an infected person was is enough to catch the disease. Some diseases require direct physical contact or even transfer of bodily fluids, such as blood, saliva, or tears. We call those 'Infectious Diseases.'

Some diseases are not contagious. For example Heart disease or Arthritis are not contagious. You cannot 'catch' arthritis or heart disease or even cancer by being around or having physical contact with someone who has these diseases.