a marketing strategy that focuses on spreading information and opinions about a product or service from person to person, especially by using unconventional means such as the Internet or email: Which online social networks can help with viral marketing?
British Dictionary definitions for viral marketing
viral marketing
noun
a direct marketing technique in which a company persuades internet users to forward its publicity material in e-mails (usually by including jokes, games, video clips, etc)
a marketing strategy in which conventional media are eschewed in favour of various techniques designed to generate word-of-mouth publicity, in the hope of creating a fad or craze
