median line

from The Collaborative International Dictionary of English v.0.48
Median \Me"di*an\ (m[=e]"d[i^]*an), a. [L. medianus, fr. medius
   middle. See {Medial}.]
   1. Being in the middle; running through the middle; as, a
      median groove.
      [1913 Webster]

   2. (Zool.) Situated in the middle; lying in a plane dividing
      a bilateral animal into right and left halves; -- said of
      unpaired organs and parts; as, median coverts.
      [1913 Webster]

   {Median line}.
      (a) (Anat.) Any line in the mesial plane; specif., either
          of the lines in which the mesial plane meets the
          surface of the body.
      (b) (Geom.) The line drawn from an angle of a triangle to
          the middle of the opposite side; any line having the
          nature of a diameter.

   {Median plane} (Anat.), the mesial plane.

   {Median point} (Geom.), the point where the three median
      lines of a triangle mutually intersect.
      [1913 Webster]
    

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