- Electricity. an electric current of constant direction, having a magnitude that does not vary or varies only slightly. Abbreviation: dc
Origin of direct current
Examples from the Web for direct current
Historical Examples of direct current
It will be necessary to obtain the use of a direct-current ammeter for this purpose.The Boy Mechanic, Book 2
This arrangement can be used with direct-current circuits only.Motion Picture Operation, Stage Electrics and Illusions
Henry C. Horstmann
The engine is belted to a direct-current generator of the shunt-wound type.Farm Mechanics
Herbert A. Shearer
The alternating-current arc-lamp was developed after the appearance of the direct-current open-arc and has been widely used.
This humming sound is quite different from the occasional hissing of a direct-current arc.
- a continuous electric current that flows in one direction only, without substantial variation in magnitudeAbbreviation: DC Compare alternating current
- An electric current that moves in one direction with constant strength. Batteries are a source of direct current. Direct current is not used for long-distance power transmission because it is difficult to step up the voltage to a level that is efficient for energy transfer and then to step the voltage back down again for safe domestic use. Compare alternating current. See Notes at current Tesla.