Dead Presidents
Description of US Currency, alluding to portraiture displayed on the notes.

Decay
The lessening of strength that occurs as waves leave a wind generation area...the fetch. It's factored into wave height predictions and models due to a known occurrence that wave trains lose a portion of their energy as they propagate. This can be due to many factors such as local area winds, shoaling, etc.

Deck
The top surface of a surfboard on which you apply wax for traction.

Deck Grip
Rough-surfaced material patch, usually a fraction of an inch thick, which can be glued to the deck of a surfboard to increase traction instead of wax.

Deep Water
Water deep enough so that surface waves are not affected by the bathymetry on the ocean bottom. Generally, water more than 1,000 feet, or at least deeper than one-half the wavelength of the existing waves is considered deep water.

Deepwater breaks
Surf spots where the swells have a steep transition from deep water to shallow water so the waves are generally bigger and more powerful than elsewhere. Also includes surf spots where the deep water bathemetry of the ocean floor can greatly focus longer period swells (over 16 seconds) to create larger and more powerful waves. Spots with underwater canyons like Blacks are a prime example.

Degrees 
A) The unit of measurement for direction to analyze where wind and swell direction is coming from. North is 0 or 360 degrees (12:00 o'clock); and then moving clockwise, east at 90 degrees (3:00 o'clock), south at 180 degrees (6:00 o'clock) and west at 270 degrees (9:00 o'clock). Northeast may be anywhere between 0 and 90 degrees, southeast between 90 and 180 degrees, southwest between 180 and 270 degrees and northwest between 270 and 360 degrees. B) Degrees also are used to measure Latitude and Longitude, with minutes and seconds used a fractionals between the degrees. One degree of Latitude will always equal 60 miles at that same location. One degree of Longitude will always vary due to the curvature of the Earth toward the poles.

Delaminate
A breakdown of the bond between the fiberglass and foam of a surfboard, where the fiberglass becomes separated from the foam. Usually caused by water seeping in under the fiberglass due to a ding of other fracture of the waterproof bond. Can also be caused by the surfboard being exposed to excessive heat like in a hot car, which will cause the foam to shrink slightly away from the fiberglass bond. Delaminations should be fixed immediately as they will spread and the surfboard strength will be weakened dramatically.

Deralict
Means cool, sick, dope. Something really cool.

Deshackulate
To be shot out of the whirling vortex of a breaking barrel with so much force that it causes you to launch from your board.

Designer
An expert surfboard shaper or rider who originates ideas for surfboard shapes. See shaper.

Dial Me In 
To impart knowledge, wisdom or simply inform someone of something.

Diffraction
The process of wave energy filtering into the lee of obstacles such as breakwaters by the transfer of the wave energy along wave crests. Diffracted waves are smaller than the original waves.

Dilude
Total jerk surfer that talks incessantly in the lineup ruining it for everyone.

Ding
Damage to surfboard caused by dropping or collision with another hard object or surfboard. Dings must be dried out and repaired immediately otherwise water will weaken the strength of the board.

Ding Dong
Used to describe an idea or something really cool. Can also be an object.