back in WordNet English dictionary

1. (American football) the position of a player on a football team who is stationed behind the line of scrimmage
   back 
   
2. the side that goes last or is not normally seen
   "he wrote the date on the back of the photograph"
   rear  back 
   
3. a support that you can lean against while sitting
   "the back of the dental chair was adjustable"
   back  backrest 
   
4. the part of a garment that covers the back of your body
   "they pinned a `kick me' sign on his back"
   back 
   
5. the protective covering on the front, back, and spine of a book
   "the book had a leather binding"
   binding  book binding  cover  back 
   
6. the posterior part of a human (or animal) body from the neck to the end of the spine
   "his back was nicely tanned"
   back  dorsum 
   
7. the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
   "the fall broke his back"
   spinal column  vertebral column  spine  backbone  back  rachis 
   
8. 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"
   back  rear 
   
9. (football) a person who plays in the backfield
   back 
   

1. establish as valid or genuine
   "Can you back up your claims?"
   back  back up 
   
2. strengthen by providing with a back or backing
   back 
   
3. shift to a counterclockwise direction
   "the wind backed"
   back 
   
4. place a bet on
   "Which horse are you backing?"; "I'm betting on the new horse"
   bet on  back  gage  stake  game  punt 
   
5. travel backward
   "back into the driveway"; "The car backed up and hit the tree"
   back 
   
6. cause to travel backward
   "back the car into the parking spot"
   back 
   
7. support financial backing for
   "back this enterprise"
   back 
   
8. be behind; approve of
   "He plumped for the Labor Party"; "I backed Kennedy in 1960"
   back  endorse  indorse  plump for  plunk for  support 
   
9. give support or one's approval to
   "I'll second that motion"; "I can't back this plan"; "endorse a new project"
   second  back  endorse  indorse 
   
10. be in back of
    "My garage backs their yard"
    back 
    

1. related to or located at the back
   "the back yard"; "the back entrance"
   back 
   
2. of an earlier date
   "back issues of the magazine"
   back 
   
3. located at or near the back of an animal
   "back (or hind) legs"; "the hinder part of a carcass"
   back  hind  hinder 
   

1. 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"
   back  backward  backwards  rearward  rearwards  back  backward  backwards  rearward  rearwards 
   
2. in or to or toward a past time
   "set the clocks back an hour"; "never look back"; "lovers of the past looking fondly backward"
   back  backward  back  backward 
   
3. 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"
   back  back 
   
4. in or to or toward a former location
   "she went back to her parents' house"
   back  back 
   
5. in or to or toward an original condition
   "he went back to sleep"
   back  back 
   
6. in reply
   "he wrote back three days later"
   back  back