noun | verb | adjective | adverb
backback1 /bæk/ noun 1 the part of your body► back the part of your body between your neck and your waist, on the opposite side from your chest and stomach: I hurt my back playing basketball with my son. She lay on her back, staring at the sky.
► spine the long set of bones that goes down the middle of your back: He injured his spine in a motorcycle accident and had to spend months in bed.
► backbone (informal) backbone means the same as spine: The cow was so thin you could see her backbone and ribs.
2 the part of something that is farthest from the front► back the part of something that is farthest from the front: The bus was crowded, but we found a few seats in the back. The T-shirt has a picture of a snake on the back. The sun had burned the back of my neck.
► rear the back of an area. Rear sounds more formal than back: There are more seats in the rear of the train. The kitchen was at the rear of the house.
► end the part of something that is farthest from the beginning. You use end about roads, hallways, lines, and other long narrow things: Go to the end of the street and turn left. We sat in silence at both ends of the long wooden table.
► stern the back part of a boat or ship: There was a rope attached to the stern of the boat, which he used to tie it to the dock.
ANTONYMS ➔ see front noun | verb | adjective | adverb
backback2 /bæk/ verb 1 to move backward► back to move backward in a particular direction, especially in order to leave a place or area: We slowly backed away from the growling dog. When she was sure the baby was asleep, she backed quietly out of the room.
► back up to move backward: Can you back up a little bit so that everyone can see?
► step back to take one step or a few steps backward: I stepped back to let the other people pass.
► retreat to walk backward or away from the direction you were walking before. Retreat sounds fairly literary, and you use it when you want to show that someone is avoiding someone or something else: He saw her and retreated up the stairs, because he was too shy to speak to her.
2 to make a vehicle go backward► back to drive a car or other vehicle backward: He carefully backed the truck into the driveway. Back the car to the end of the street and turn around. ➔ GRAMMAR: Back is always followed by a prepositional phrase, for example "back into something."
► back up back up means the same as back: I couldn’t back up because another car was parked very close behind me.
► put a car/truck, etc. in reverse if you put a vehicle in reverse, you change the gear so that you can drive backward: He started the car, put it in reverse, and then backed out of the parking space.
➔ see invest support noun | verb | adjective | adverb
backback3 /bæk/ adjective ► back at the back of something: We were sitting in the back row of the theater. Kara walked around the house to the back door. The back pocket of your jeans is ripped. ➔ GRAMMAR: Back is only used before a noun: the back seat.
► rear relating to the back part of a building, vehicle, ship, or airplane. Rear sounds more formal than back: Passengers should exit through the rear door of the bus. ➔ GRAMMAR: Rear is only used before a noun: the rear window of the car
► backward toward the direction that is behind you: I remember that she gave us a backward look and a little wave when she left. ➔ GRAMMAR: Backward is only used before a noun: The gymnast did a backward somersault.
noun | verb | adjective | adverb
backback4 /bæk/ adverb 
► back adverb toward a place behind you: He looked back over his shoulder. I stepped back to let them pass.
► backward also backwards adverb toward a place behind you, but while facing forward: She slipped and fell backward into the snow. Can you skate backwards?
ANTONYMS ➔ see forward1