Definition of Dielectric

A dielectric is an insulating material that does not conduct electric current. It has the ability to store electrical energy in an electric field when subjected to voltage, causing the formation of an electric field within the material. Dielectrics are commonly used in capacitors and various electrical devices to prevent current flow and isolate electrical components.


The phonetic pronunciation of the keyword “Dielectric” is: /daɪˌɪlɛkˈtrɪk/ It can be broken down into syllables as di·e·lec·tric.

Key Takeaways

  1. Dielectrics are insulating materials that do not conduct electricity but can support an electrostatic field, enhancing the energy storage capabilities of capacitors.
  2. Dielectric materials have a dielectric constant that quantifies their ability to store electrical energy in an electric field. Materials with higher dielectric constants result in larger capacitance for capacitors using those materials.
  3. Dielectrics exhibit polarization when exposed to an electric field, causing the formation of electric dipoles. This polarization leads to a reduction in the overall electric field within the dielectric and enhances energy storage within capacitors.

Importance of Dielectric

The term dielectric is important in technology because it pertains to the ability of a material to resist the flow of electrical current while effectively storing energy in an electric field.

Dielectric materials are essential in various applications such as insulators in electronic devices, transformers, and capacitors.

They help to prevent energy loss, enable efficient energy storage, and improve the overall performance and reliability of electronic components.

By understanding and utilizing dielectric properties, engineers and scientists can develop materials that optimize functionality in electronic systems and expand the potential developments in the field of technology.


Dielectric materials play a critical role in the world of electronics and electrical systems. Their primary purpose is to support and enhance the functionality of capacitors, which are essential components in the storage and release of electrical energy. Dielectric materials specifically allow capacitors to operate effectively by acting as an insulating medium between the conductive plates, preventing the flow of electrical current between them.

This is crucial in allowing the capacitor to store an electric charge and maintain a voltage, contributing to the stability and efficiency of various electronic devices. Additionally, high-quality dielectric materials exhibit excellent insulating properties, making them ideal for use in high voltage applications, power distribution systems, and electrical insulation. Another important application of dielectric materials is in the manufacturing of printed circuit boards (PCBs) where they act as a substrate to support the various electronic components and conductive pathways.

A well-designed dielectric layer is critical to the performance of the PCB, as it can help reduce signal losses, improve electrical insulation, and minimize crosstalk between adjacent circuits. Dielectric materials are also employed as protective coatings in electronic devices, as they often exhibit thermal and chemical stability that aids in preserving the longevity and functionality of sensitive electronic components. Furthermore, dielectric materials are used in the production of microelectromechanical systems (MEMS), microwave components, and various other applications throughout the technology sector that rely on the materials’ unique insulating and electrical characteristics.

Examples of Dielectric

Dielectric materials are crucial components in various technologies and applications due to their ability to store energy and act as insulators without conducting electricity. Here are three real-world examples of dielectric technology in use:

Capacitors: Dielectric materials are a critical part of capacitors, which are crucial components in electronic systems. Capacitors are used in power supplies, signal filtering, energy storage, and other electronic circuitry. In a capacitor, the dielectric material is sandwiched between the metal plates to store energy. The material’s dielectric constant and its ability to minimize electrical conduction make it a valuable component in capacitor design.

Antennas and transmission lines: In many types of antennas, such as patch antennas, dielectric materials are used as substrates to separate the conducting layers. These materials help in maintaining a specific geometry and improving the performance of the antennas. Additionally, dielectric materials are utilized in the insulation layers of coaxial cables and waveguides that are used in telecommunications and radar systems. They help minimize energy loss and signal distortion during the transmission of electromagnetic signals.

Electrical insulation: Dielectric materials are widely used in high voltage equipment such as transformers, generators, circuit breakers, and other power transmission and distribution systems. They act as electrical insulators, preventing the conduction of electric current between different components by maintaining a high resistance. This is particularly important to prevent short circuits and maintain safety in electrical systems. Examples of dielectric materials used in electrical insulation include ceramics, polymers, and glass.

Dielectric FAQ

1. What is a dielectric?

A dielectric is a non-conductive material, typically an insulator, that can store electrical energy when an external electric field is applied. These materials have low electrical conductivity and high ability to resist electric currents.

2. What are some common examples of dielectric materials?

Common examples of dielectric materials include glass, ceramics, plastics, rubbers, paper, and certain gases, such as air and dry nitrogen.

3. What is the significance of dielectric constant?

The dielectric constant of a material is a measure of its ability to store electrical energy in an electric field compared to a vacuum. It is an important property of dielectric materials and helps in determining their suitability for specific applications.

4. What is the role of dielectric materials in capacitors?

Dielectric materials play a crucial role in the construction of capacitors. They act as insulators between the conductive plates of a capacitor, preventing the flow of direct current (DC) while allowing alternating current (AC) to pass through. The dielectric material also influences the capacitor’s ability to store electrical energy.

5. How does temperature affect dielectric properties?

Temperature has a significant impact on the dielectric properties of materials. In general, as the temperature increases, dielectric constant and dissipation factor also increase, which can lead to reduced efficiency and possible breakdown of the dielectric material. Therefore, it is essential to consider the temperature range a dielectric material will be exposed to in its intended application.

Related Technology Terms

  • Dielectric constant
  • Dielectric strength
  • Dielectric loss
  • Dielectric breakdown
  • Capacitor

Sources for More Information


About The Authors

The DevX Technology Glossary is reviewed by technology experts and writers from our community. Terms and definitions continue to go under updates to stay relevant and up-to-date. These experts help us maintain the almost 10,000+ technology terms on DevX. Our reviewers have a strong technical background in software development, engineering, and startup businesses. They are experts with real-world experience working in the tech industry and academia.

See our full expert review panel.


About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

Technology Glossary

Table of Contents

More Terms