Final answer:
A pandemic is an epidemic of infectious disease that spreads over a wide geographic area, often across multiple populations or continents. It affects a very high proportion of the population and can even spread worldwide.
Step-by-step explanation:
A pandemic is an epidemic of infectious disease that spreads over a wide geographic area, often across multiple populations or continents. It affects a very high proportion of the population and can even spread worldwide.
An example of a pandemic is the Black Death (bubonic plague) that spread throughout Europe and much of Asia in the 14th century. Other modern examples include HIV/AIDS and novel influenza virus strains.