The meaning of VIRAL is of, relating to, or caused by a virus. How to use viral in a sentence. viral adjective (INTERNET) used to describe something that quickly becomes very popular or well known by being published on the internet or sent from person to person by email, phone, etc.: 1. Of, relating to, or caused by a virus. 2. Of or relating to the rapid propagation of information, ideas, or trends by means of social networks rather than conventional mass media: viral marketing. used to describe a piece of information, a video, an image, etc. that is sent rapidly over the internet and seen by large numbers of people within a short time. Within 24 hours, the video went viral on YouTube and Facebook. Definition of viral adjective in Oxford Advanced Learner's Dictionary. The word Viral means "relating to viruses " (small infectious agents). It may also refer to: Memetic behavior likened that of a virus, for example: 6 days ago · Yet again, something dreadful and new which he doesn't understand is going viral. Today's fad is, you paint a black vertical rectangle on the wall, or on a mirror, or over the top of a picture. Discover the meaning of Viral, explore its usage in everyday language, popular idioms, and fun facts that make this word fascinating. Perfect for learners and curious minds! viral, adj. meanings, etymology, pronunciation and more in the Oxford English Dictionary VIRAL definition: of, relating to, or caused by a virus. See examples of viral used in a sentence. VIRAL meaning: 1 : caused by a virus; 2 : spreading very quickly to many people especially through the Internet