“Pandemic” means “widespread” – that is, covering a large geographic area and affecting many people. You’ll usually hear this in relation to an illness. In fact, an epidemic is promoted to “pandemic” status when it spreads beyond the usual range of infection. For example, the so-called ‘bird flu’ is considered an epidemic if it affects many people in one country, but if it spreads across the globe, it will become pandemic.

Example: “With all of the air travel being done these days between continents, medical researchers are afraid that some diseases may become pandemic if people return home after being infected.”