Antenna (6)
'antenna' is the definition.
(synonyms)
This is all the clue.
(Other definitions for aerial that I've seen before include "Signal receiver" , "Device to receive or transmit radio waves" , "imaginary" , "Ethereal" , "Antenna; of the air" .)
'antenna' is the definition.
(I know that antenna can be written as feeler)
This is the entire clue.
(Other definitions for feeler that I've seen before include "Tentative proposal (to test someoneOs attitude)" , "Antenna or cautious proposal" , "Organ of touch or tentative proposal" , "Tentative suggestion designed to elicit the reactions of others" , "Insect's antenna" .)