Short for Rebekah. Reserved for only the coolest of Rebekahs. Whenever something is not going really or perhaps is hard To pour one's food over oneself(for example. to give your boobs/moo) Bek is a nickname for Becky which is a nickname for Rebecca that is a nickname for Parker's mother from tiverton, ri Circa: mid 1990s, distributed in proletariate areas of Belfast.Definition: an even more formal form of your message 'back once again'. 'Back' is often considered slang for bek into uninformed members of public.Bek is generally used in conjunction with equally well-known word Nek in an exceedingly sexy definition. Licking of any area of the reduced bek, and continuing to run your tongue towards 'nek' is definitely the highest type of sexual functions by many people.