Definition of viral
- a viral infection
- a viral video
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'viral.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: caused by a virus
: spreading very quickly to many people especially through the Internet
What made you want to look up viral? Please tell us where you read or heard it (including the quote, if possible).
Confusing Words—A Quiz