n, pl  sca*le*ni   :  any of usu. three deeply situated muscles on each side of the neck of which each extends from the transverse processes of two or more cervical vertebrae to the first or second rib:  a  :  one arising from the transverse processes of the third to sixth cervical vertebrae, inserting on the scalene tubercle of the first rib, and functioning to bend the neck forward and laterally and to rotate it to the side - called also anterior scalene , calenus anterior , calenus anticus   b  :  one arising from the transverse processes of the lower six cervical vertebrae, inserting on the upper surface of the first rib, and functioning similarly to the scalenus anterior - called also middle scalene , calenus medius   c  :  one arising from the transverse processes of the fourth to sixth cervical vertebrae, inserting on the outer surface of the second rib, and functioning to raise the second rib and to bend and slightly rotate the neck - called also posterior scalene , calenus posterior  .
 
 
 
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