What does capacitor mean?
A capacitor is a fundamental component of modern electronics that stores electrical energy in the form of an electric field. In its simplest form it consists of two conductive plates separated by an insulating material called a dielectric; when connected to a voltage source, opposite charges accumulate on the plates, and this stored charge can later be released back into a circuit. Capacitors are used to smooth power supplies, filter signals, tune radios, time circuits, and deliver sudden bursts of energy, as in camera flashes. The word entered English in the early twentieth century as electrical engineering matured, deriving from Latin capere (to take or hold) via capacity — a fitting lineage for a device that literally holds charge. The older synonym condenser persists mainly in British usage and historical texts.
nounA passive electronic component that stores electrical energy in an electric field between a pair of conductors separated by an insulating material, typically used to smooth, filter, or temporarily store charge in circuits.
- An electrical component that stores energy as an electric charge between two conducting plates separated by an insulator (dielectric).
"The technician replaced the swollen capacitor on the motherboard and the computer booted normally again."
"A large electrolytic capacitor across the power supply smoothed out the voltage fluctuations."
"The flash on a camera charges its capacitor for several seconds before it can fire."
Standard regular plural; used freely when referring to multiple components.
"The repair kit included assorted resistors and capacitors."
The capacitor was invented by accident: Ewald Georg von Kleist and Pieter van Musschenbroek independently discovered it in 1745-46 while trying to 'store electricity' — van Musschenbroek said a jolt from his Leyden jar made him feel like he might die.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of capacitor
The word capacitor derives from Latin capere, meaning "to take" or "to hold," via capax/capacitas, the root also underlying capacity and capable. It arose in the early twentieth century from earlier terms such as capacity and condenser, coined to name a device whose defining property is storing electrical charge. Its German cognate Kondensator reflects the parallel tradition of calling the device a condenser, a term still common in older British literature.
How capacitor is actually used
Capacitor is a technical term used mainly in electronics, engineering, and physics; in everyday British English the older term condenser survives informally among radio hobbyists. It is a countable noun with standard plural capacitors.
Easily confused with capacitor
Capacity is the amount something can hold or contain, while a capacitor is a physical electronic component that stores electrical charge.