(n) the position of a player on a football team who is stationed behind the line of scrimmage
(n) a support that you can lean against while sitting; "the back of the dental chair was adjustable"
(n) the part of a garment that covers your back; "they pinned a `kick me' sign on his back"
(n) the front and back covering of a book; "the book had a leather binding"
(n) the side that goes last or is not normally seen; "he wrote the date on the back of the photograph"
(n) the posterior part of a human (or animal) body from the neck to the end of the spine; "his back was nicely tanned"
(n) the series of vertebrae forming the axis of the skeleton and protecting the spinal cord; "the fall broke his back"
(n) the part of something that is furthest from the normal viewer; "he stood at the back of the stage"; "it was hidden in the rear of the store"
(n) (football) a person who plays in the backfield
(v) strengthen by providing with a back or backing
(v) establish as valid or genuine; "Can you back up your claims?"
(v) shift to a counterclockwise direction; "the wind backed"
(v) place a bet on; "Which horse are you backing?"; "I'm betting on the new horse"
(v) travel backward; "back into the driveway"; "The car backed up and hit the tree"
(v) cause to travel backward; "back the car into the parking spot"
(v) support financial backing for; "back this enterprise"
(v) be behind; approve of; "He plumped for the Labor Party"; "I backed Kennedy in 1960"
(v) give support or one's approval to; "I'll second that motion"; "I can't back this plan"; "endorse a new project"
(v) be in back of; "My garage backs their yard"
(r) in or to or toward a past time; "set the clocks back an hour"; "never look back"; "lovers of the past looking fondly backward"
(r) at or to or toward the back or rear; "he moved back"; "tripped when he stepped backward"; "she looked rearward out the window of the car"
(r) in repayment or retaliation; "we paid back everything we had borrowed"; "he hit me and I hit him back"; "I was kept in after school for talking back to the teacher"
(r) in or to or toward a former location; "she went back to her parents' house"
(r) in or to or toward an original condition; "he went back to sleep"
(r) in answer; "he wrote back three days later"; "had little to say in reply to the questions"