Learner's definition of ANTENNA
1 : a thin sensitive organ on the head of an insect, crab, etc., that is used mainly to feel and touch things — sometimes used figuratively
◊ The plural of antenna in this sense is usually antennae.
2 chiefly US : a device (such as a wire or a metal rod) for sending or receiving radio or television signals
◊ The plural of antenna in this sense is usually antennas.