[noun] [C] - abbreviation for Internet service provider: a company that provides access to the Internet, enables you to use e-mail, and gives you space on the Internet to display documentsSome ISPs are free, give you as many e-mail addresses as you want, and 20Mb of web space.
ISP
Meaning of ISP in English
Cambridge English vocab. Кембриджский английский словарь. 2012