buttock

/ˈbʌtək/
noun
  1. Either of the two rounded fleshy parts on the lower back of the human body, formed by the gluteal muscles.
    • The doctor gave her a shot in the upper part of her buttock.
    • She felt a sharp pain in her left buttock during the long bike ride.
    • He landed hard on his right buttock after slipping on the ice.
Synonyms
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