From Latin extra mittere.
extramission (plural extramissions)
- (obsolete) Emission.
1646, Sir Thomas Browne, Pseudodoxia Epidemica, III.7:Aristotle, Alhazen, Vitello, and others [...] hold, that sight is made by reception, and not by extramission; by receiving the rays of the object into the eye, and not be sending any out.