The phrase "fin antenna" refers to a type of antenna that looks like a fin, similar to the one on a shark or a car's roof. It is used to receive or transmit signals wirelessly, like for television or radio. Full definition
The 2014 CT 200h looks faster thanks to aero - stabilizing fins having been added on tail lamps and side mirrors, and a new shark fin antenna replacing the post antenna. (japanesesportcars.com)
Distinctive dual shark fin antennas help mark the facelifted Evoque out from earlier examples (carbuyer.co.uk)
Rounding things out is a shark - fin antenna up top that replaces the small, black antenna on last year's model. (topspeed.com)