Definition
DESIGNATED COMMON TRAFFIC ADVISORY FREQUENCY (CTAF) AREA
In Alaska, in addition to being designated for the purpose of carrying out airport advisory practices while operating to or from an airport without an operating airport traffic control tower, a CTAF may also be designated for the purpose of carrying out advisory practices for operations in and through areas with a high volume of VFR traffic.
Source: FAA Pilot/Controller Glossary (verbatim from the Federal Aviation Regulations).