Source : Webster's Revised Unabridged Dictionary (1913)

Intromission \In`tro*mis"sion\, n. [Cf. F. intromission. See
   {Intromit}.]
   1. The act of sending in or of putting in; insertion.
      --South.

   2. The act of letting go in; admission.

   3. (Scots Law) An intermeddling with the affairs of another,
      either on legal grounds or without authority.

Source : WordNet®

intromission
     n : the act of putting one thing into another [syn: {insertion},
          {introduction}]