Dispersion - The spatial property of being scattered about over an area or volume
Category: - Risk

Dispersion Algorithm - A MARIS algorithm to spread simulated traffic over a feasible region, such as a fishing ground.
Category: - General

Displacement - The total weight of the ship when afloat, including everything on board, (equals weight of water displaced.) Usually expressed in long tons.
Category: - Maritime

Distress - A search and rescue incident where there is a reasonable certainty that one or more individuals are threatened by grave and imminent danger and require immediate assistance. "Détresse"
Category: - Maritime - Risk

Distress Beacon - A generic term used to describe any emergency locator transmitter (ELT), emergency position-indicating radio beacon (EPIRB) or personal locator beacon (PLB). "balise de détresse"
Category: - Maritime - Risk

Ditching - Ditching refers to two things in SAR: when an aircraft is forced to do an emergency landing in the water, it is said to have ditched "amerissage forcé"; the SAR Techs will often refer to ditching when they talk about removing their SCUBA tanks and equipment under water. If a diver becomes entangled in under water debris, often the only way to disentangle him or her self is by ditching their gear.
Category: - Maritime - Risk

DMB - Datum Marker Buoy’s are small waterproof radio transmitters, dropped from helicopters, airplanes or boats, which are used to mark the location of floating debris. The DMBs drift at or near the same speed as the actual sea current, enabling ships and aircraft to track the drift of the debris or to serve as location reference."bouée-repère électronique"
Category: - Acronym - SAR

DND - Department of National Defence, Canada
Category: - Risk - Acronym

DOD - Department of Defense, USA
Category: - Risk - Acronym

Dog - A small bent metal fitting used in closing doors, hatch covers, manhole covers, etc.; a bent bar of round iron used in holding shapes on bending slab; any small flat lug temporarily welded to structure as backing for a wedge.
Category: - Maritime