What is the meaning of dispersion?

(DoD) In naval control of shipping, the reberthing of a ship in the periphery of the port area or in the vicinity of the port for its own protection in order to minimize the risk of damage from attack. See also circular error probable; convoy dispersal point; delivery error; deviation; dispersion error; horizontal error.
(DoD, NATO) A scattered pattern of hits around the mean point of impact of bombs and projectiles dropped or fired under identical conditions.
(DoD, NATO) In antiaircraft gunnery, the scattering of shots in range and deflection about the mean point of explosion.
(DoD, NATO) In airdrop operations, the scatter of personnel and/or cargo on the drop zone.
(DoD, NATO) In chemical and biological operations, the dissemination of agents in liquid or aerosol form.
(DoD, NATO) The spreading or separating of troops, materiel, establishments, or activities which are usually concentrated in limited areas to reduce vulnerability.