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Displacement Current

An expression for the effective current flow across a capacitor.

Display Terminal

An output device, such as a CRT, that produces a visual representation of graphic data.

Disposable Cylinder

A container for the one-time use of packaging, transporting, and dispensing of a fluid, such as refrigerant. It is a violation of Federal Law to refill these cylinders, commonly referred to as "DOT-39s."

Disposal

To get rid of something.

Disqualified

1. To render unfit. 2. To be deprived of a right or privilege.

Dist

An abbreviation for distributor.

Distance Learning

A type of education in which students work on their own at home or at the office and communicate with faculty and other students via email, electronic forums, video conferencing, and other forms of computer-based communication.

Distillation

The process that consists of driving gas or vapor from liquids or solids by heating and condensing . Used for purification, fractionation, or the formation of new substances.

Distillation Curve

The reference to plotting a line connecting the percentages of gasoline that evaporate at various temperatures. The distillation curve is used as an important control for fuel standards such as volatility (vaporization).

Distillation Endpoint

The temperature at which a fuel is completely vaporized.

Distortion

1. Inaccuracies in size and shape, as in an out-of-round cylinder. 2. An unwanted change in purity of sound, as caused by a weak signal. 3. A term used for tread distortion.

Distributor

1. A jobber; one who buys from a manufacturer and sells to a wholesaler. 2. A device used to direct electrical current to spark plugs. 3. A device used to direct fuel to injectors.

Distributor

An ignition system component on virtually all vintage vehicles and some late-model vehicles. The distributor rotates via a gear on the camshaft and triggers the ignition. The coil then fires, sending its power back to the distributor through the coil wire. Next, the distributor literally distributes the spark from the coil to the appropriate spark plug wire, according to the engine's firing order. Many new vehicles feature a distributorless ignition system.

Distributor Advance

A term used for centrifugal advance, ignition advance, or vacuum advance.

Distributor Cam

The four-, six-, or eight-sided lobe at the top end of the distributor shaft that rotates to cause the contact points to open and close.

Distributor Cap

A cover for the conventional ignition-system distributor, having a central terminal that receives secondary voltage from the coil and four, six, or eight peripheral terminals to send this voltage to the spark plugs.

Distributor Housing

A metal part that contains or provides a mounting for distributor components in a conventional ignition system.

Distributor Ignition

An ignition system that relies on a conventional distributor for proper operation.

Distributor Pipe

A pipe to convey fuel from the fuel distributor to the injector.

Distributor Plate

The plate inside a distributor that is fastened to the housing and does not move.