\Com*mis"sure\ (? or ?; 134-6), n. [L. commissura a
joining together: cf. F. commissure. See {Commit}.]
1. A joint, seam, or closure; the place where two bodies, or
   parts of a body, meet and unite; an interstice, cleft, or
   juncture.
2. (Anat. & Zo["o]l.)
   (a) The point of union between two parts, as the angles of
       the lips or eyelids, the mandibles of a bird, etc.
   (b) A collection of fibers connecting parts of the brain
       or spinal marrow; a chiasma.
3. (Bot.) The line of junction or cohering face of two
   carpels, as in the parsnip, caraway, etc.