[1] : The Collaborative International Dictionary of English v.0.48

mesial \me"sial\ ?; 277, a. gr. me`sos middle. anat.
   middle; median; in, or in the region of, the mesial plane;
   internal; -- opposed to lateral.
   1913 webster

   mesial plane. anat. see meson.
      1913 webster
see also:
lateral mesial plane meson 

[2] : WordNet (r) 2.0

mesial
     adj : being in or directed toward the midline or mesial plane of
           the body ant: distal
see also:
distal 

Mesial >> M Words
Mesial, definition of term: Mesial
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