Pandemic
An epidemic occurring over a very wide area (countries or continents) and usually affecting a large proportion of the population (human and/or animals).
Glossary Source
JRC EU CBRNe Glossary
(
EU Glossary on Chemical, Biological, Radiological, Nuclear, and Explosive risks
)
https://publications.jrc.ec.europa.eu/repository/bitstream/JRC128863/JRC128863_01.pdf