Why was "tantrum" trending last week?
(LEC) A company allowed to handle local calls following the break-up of the Bell system in the US by anti-trust regulators. These vary from Regional Bell Operating Companies (RBOC) through to small independents such as Farmers Cooperative.
Local exchange carriers are not allowed to handle long-distance traffic. This is handled by inter-exchange carriers (IXC) who are not allowed to handle local calls.