seatback

/ˈsiːtˌbæk/
noun
  1. The upright part of a chair or seat that supports a person's back.
    • The airline passenger put a pillow behind the seatback for extra support.
    • She adjusted the seatback to a more comfortable angle before the movie started.
    • He leaned the seatback all the way down to take a nap during the long drive.
Synonyms
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