plural antennae /ænˈtɛni/ or antennas
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
a Senator with sensitive political antennae [=a Senator who is very aware of political issues and attitudes]
◊ 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
a TV antenna [=(chiefly British) aerial]
◊ The plural of antenna in this sense is usually antennas.