Definition
INTERMEDIATE LANDING
On the rare occasion that this option is requested, it should be approved. The departure center, however, must advise the ATCSCC so that the appropriate delay is carried over and assigned at the intermediate airport. An intermediate landing airport within the arrival center will not be accepted without coordination with and the approval of the ATCSCC.
Source: FAA Pilot/Controller Glossary (verbatim from the Federal Aviation Regulations).