TEFC
A TEFC enclosure on a motor means "Totally Enclosed, Fan Cooled".
This motor is probably the most commonly used motor in ordinary industrial environments. It costs only a few dollars more than the open motor, yet offers good protection against common hazards.
The motor is constructed with a small fan on the rear shaft of the motor, usually covered by a housing. This fan draws air over the motor fins, removing excess heat and cooling the motor. The enclosure is "Totally Enclosed". This ordinarily means that the motor is dust tight, and has a moderate water seal as well. Notice that TEFC motors are not secure against high pressure water. For these applications, consider the "wash down" motor, which is usually designed to withstand regular washing, such as found in a food processing facility
TEFC stands for Totally Enclosed, Fan-Cooled and refers to an industrial electric motor equipped with an external fan to circulate outside air to the motor.
Compare to ODP (Open Drip Proof motor)