Lewis & Short

ēmissĭo, ōnis, f. [id.; sent out, put forth; hence], a sending out, darting forth (rare).

  1. I. Prop., a letting go: radiorum ex oculis, a darting forth, Gell. 5, 16, 2: mortui sunt in emissione, in exile, Vulg. Baruch. 2, 25.
  2. * II. Meton., power of projecting or hurling; in plur.: graviores telorum, Cic. Tusc. 2, 24, 57; a letting go, releasing: anguis, id. Div. 2, 29, 62 (thrice).