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Medical Dictionary

axis

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noun ax·is \ˈak-səs\

Medical Definition of axis

plural ax·es \-ˌsēz\play

  1. 1a:  a straight line about which a body or a geometric figure rotates or may be thought of as rotatingb:  a straight line with respect to which a body, organ, or figure is symmetrical

  2. 2a:  the second vertebra of the neck of the higher vertebrates that is prolonged anteriorly within the foramen of the first vertebra and united with the dens which serves as a pivot for the atlas and head to turn upon—called also epistropheusb:  any of various central, fundamental, or axial parts <the cerebrospinal axis> <the skeletal axis>c:  axilla





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