n.
the posterior part of a human (or animal) body from the neck to the end of the spine
"his back was nicely tanned"
同义词：dorsum
the side that goes last or is not normally seen
"he wrote the date on the back of the photograph"
同义词：rear
the part of something that is furthest from the normal viewer
"he stood at the back of the stage"
同义词：rear
(football) a person who plays in the backfield
the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
"the fall broke his back"
同义词：spinal columnvertebral columnspinebackbonerachis
the protective covering on the front, back, and spine of a book
同义词：bindingbook bindingcover
the part of a garment that covers the back of your body
"they pinned a `kick me' sign on his back"
a support that you can lean against while sitting
"the back of the dental chair was adjustable"
同义词：backrest
the position of a player on a football team who is stationed behind the line of scrimmage
