From Longman Business Dictionary
B2BB2B adjectiveadj, adverbadv COMMERCECOMPUTINGbusiness-to-business; B2B buying, selling, exchanging information etc is done between companies on the Internet, rather than between companies and customersFor more information about our B2B Marketing Services, call this number.
—B2B noun [uncountableU]B2B is a huge growth area.