back radio echo

back Preposition

— Toward the rear. He went back behind the stands. — To a place again. I didn't like it, so I sent it back. He went back to the same house. They came back again.

back Noun

— The back is the rear part of something; it is the part in the other direction from the front. I went to the back of the house. — The back is the rear part of the human body. He had a scar on his back.

back Verb

— If you back something, you support it. The Republicans backed the bill. — If you back up, you move backward. He put the car in gear and backed right into the garage door.

radio Noun

— A radio is piece of electronic equipment that sends or receives signals though the air and plays voice, music, or other sounds. I used to carry a small radio, but now I have an MP3 player. When I'm in the car, I usually listen to the radio. The news will be on the radio in about five minutes. CBC 99.1 FM is my favorite radio station. The pilot tried to contact the airport over the radio.

radio Verb

— If you radio someone, you send a message to them using a radio. — If you radio a message, you send it to someone using a radio.

echo Noun

— A reflected sound that is heard again by a person. — The letter E in the ICAO spelling alphabet.

echo Verb

— To repeat back what someone else has just said.