noun (n)

• the act of twisting or deforming the shape of something (e.g., yourself)(noun.act)

  Synonym:
  deformation
  

  source: wordnet30
• a tortuous and twisted shape or position(noun.shape)

  Example:
  The acrobat performed incredible contortions.
  

  Synonym:
  crookedness, torsion, tortuosity, tortuousness
  

  source: wordnet30
• A twisting; a writhing; wry motion; a twist; as, the contortion of the muscles of the face.(noun)

  source: webster1913