Electrical, Electronic & Connector Terms Glossary
This glossary explains common electrical, electronic, and connector-related terms in plain English. It is designed as a practical reference for engineers, buyers, salespeople, technicians, students, and anyone working with electronic interconnect products, components, circuits, and specifications.
Electrical Basics
Voltage
Electrical pressure that pushes current through a circuit. Voltage is measured in volts.
Current
The flow of electrical charge through a conductor. Current is measured in amperes, often called amps.
Resistance
The opposition to current flow in a circuit. Resistance is measured in ohms.
Power
The rate at which electrical energy is used or transferred. Power is measured in watts.
Circuit
A complete path that allows electricity to flow from a source, through a load, and back again.
Load
The device or component that uses electrical power, such as a motor, light, sensor, or circuit board.
Source
The origin of electrical energy in a circuit, such as a battery, power supply, generator, or outlet.
Conductor
A material that allows electrical current to flow easily. Copper and aluminum are common conductors.
Insulator
A material that resists current flow. Plastic, rubber, glass, and ceramic are common insulating materials.
Ground
A reference point in an electrical circuit, often used for safety, shielding, or signal reference.
Earth Ground
A physical connection to the earth, commonly used for safety in electrical systems.
Chassis Ground
A ground connection tied to the metal frame or enclosure of equipment.
Open Circuit
A broken or incomplete circuit path where current cannot flow.
Short Circuit
An unintended low-resistance path that allows excessive current to flow, often causing heat, damage, or tripped protection.
Polarity
The positive and negative orientation of an electrical connection. Reversing polarity can damage some devices.
Continuity
An unbroken electrical path. A continuity test checks whether two points are electrically connected.
Electronic Components
Resistor
A component that limits or controls current flow in a circuit.
Capacitor
A component that stores electrical energy and can smooth voltage, filter signals, or block direct current.
Inductor
A coil-like component that stores energy in a magnetic field and resists changes in current.
Diode
A component that generally allows current to flow in one direction while blocking it in the opposite direction.
LED
A light-emitting diode that produces light when current flows through it.
Transistor
A semiconductor device used to switch or amplify electrical signals.
Relay
An electrically controlled switch used to turn another circuit on or off.
Fuse
A safety device designed to open a circuit when current exceeds a rated level.
Switch
A device that opens or closes a circuit to control current flow.
Sensor
A device that detects a physical condition such as temperature, pressure, light, motion, or position.
Transformer
A device that transfers electrical energy between circuits, often changing voltage levels.
Rectifier
A circuit or component that converts alternating current into direct current.
Voltage Regulator
A component or circuit that maintains a steady output voltage.
Integrated Circuit
A small electronic chip that contains many components such as transistors, resistors, and logic circuits.
Microcontroller
A small computer-on-a-chip used to control devices, sensors, displays, motors, and embedded systems.
Connector & Interconnect Terms
Connector
A device used to join electrical circuits together in a removable or serviceable way.
Interconnect
A broad term for products and systems that connect electrical or electronic circuits together.
Pitch
The center-to-center spacing between adjacent contacts or pins in a connector.
Position Count
The number of contact locations or circuits in a connector.
Circuit Size
Another way to describe the number of electrical paths or positions in a connector.
Housing
The plastic or insulating body that holds terminals, contacts, or pins in place.
Header
A connector, usually mounted to a printed circuit board, that mates with a plug or receptacle.
Plug
A connector half that mates with a receptacle, jack, header, or socket. Exact usage can vary by manufacturer.
Receptacle
A connector half designed to receive or mate with another connector. Exact usage can vary by product family.
Socket
A contact or connector designed to receive a pin, post, or mating component.
Contact
The conductive part inside a connector that carries electrical current or signal.
Terminal
A conductive connector component attached to a wire or circuit to make an electrical connection.
Pin
A male conductive contact that mates with a socket or receptacle contact.
Crimp
A mechanical connection made by compressing a terminal around a wire conductor.
Solder Cup
A small cup-shaped contact area where a wire is soldered to a connector.
IDC
Insulation displacement connection. A termination method where a contact pierces wire insulation to make connection.
Mating Half
The connector part designed to plug into or connect with another connector part.
Keying
A mechanical feature that helps prevent the wrong connector from being mated.
Polarization
A design feature that helps ensure a connector is inserted in the correct orientation.
Latch
A locking feature that helps keep two connector halves mated.
Retention
The ability of a connector, terminal, or contact to stay secured in place.
Strain Relief
A feature that reduces stress on wires, cables, or terminations where they enter a connector.
Backshell
An accessory on the back of a connector that can provide protection, strain relief, shielding, or cable support.
Blind Mate
A connector design that allows mating when the user cannot clearly see or manually align both connector halves.
Board-to-Board Connector
A connector system used to connect one printed circuit board to another.
Wire-to-Board Connector
A connector system used to connect wires or a cable assembly to a printed circuit board.
Wire-to-Wire Connector
A connector system used to join one wire or cable assembly to another.
Terminal Block
A connector used to terminate and connect wires, commonly found in industrial and control applications.
Wire & Cable Terms
Wire
A single electrical conductor, usually covered with insulation.
Cable
Two or more conductors grouped together, usually inside an outer jacket.
AWG
American Wire Gauge. A standard used to describe wire size. Smaller AWG numbers generally mean larger wire.
Conductor
The metal portion of a wire or cable that carries electrical current.
Stranded Wire
Wire made from many small strands of metal, making it more flexible than solid wire.
Solid Wire
Wire made from one solid conductor, often used where flexibility is less important.
Insulation
The protective non-conductive material around a conductor.
Jacket
The outer protective covering around a cable.
Shield
A conductive layer around wires or cables used to reduce electrical noise or interference.
Drain Wire
An uninsulated or tinned wire in a shielded cable that helps connect the shield to ground.
Twisted Pair
Two insulated conductors twisted together to help reduce electromagnetic interference.
Coaxial Cable
A cable with a center conductor, insulation, shield, and jacket, commonly used for RF signals.
Ribbon Cable
A flat cable with multiple parallel conductors, often used with IDC connectors.
Cable Assembly
A completed cable with connectors, terminals, labels, or other components attached.
Wire Harness
A group of wires or cables organized and assembled to route power or signals within equipment.
Ferrule
A metal sleeve crimped onto stranded wire to improve termination in screw or clamp-style terminals.
Lug
A terminal used to connect a wire to a stud, bolt, busbar, or equipment terminal.
Ring Terminal
A terminal with a closed ring used to secure a wire under a screw or stud.
Spade Terminal
A fork-shaped terminal that can be installed or removed from a screw or stud without fully removing the fastener.
PCB & Assembly Terms
PCB
Printed circuit board. A board that mechanically supports and electrically connects electronic components.
Pad
A metal area on a PCB where a component lead, terminal, or contact is soldered.
Trace
A conductive copper path on a printed circuit board.
Via
A plated hole that connects copper layers inside a printed circuit board.
Through-Hole
A mounting style where component leads or connector pins pass through holes in the PCB.
Surface Mount
A mounting style where components are soldered directly to pads on the surface of the PCB.
Solder
A metal alloy used to join electronic components or connectors to a circuit board or wire.
Solder Joint
The physical and electrical connection made by solder between parts.
Reflow Soldering
A process where solder paste is heated to attach surface mount components to a PCB.
Wave Soldering
A soldering process where a PCB passes over a wave of molten solder, often used for through-hole components.
Pick and Place
An automated process that places electronic components onto a PCB before soldering.
Footprint
The PCB land pattern or layout required for a specific component or connector.
Land Pattern
The arrangement of pads and holes on a PCB used to mount a component.
Panelization
The process of arranging multiple PCBs in one larger manufacturing panel.
Power & Current Terms
Current Rating
The amount of current a connector, wire, or component can carry under specified conditions.
Voltage Rating
The maximum voltage a component or connector is designed to safely handle under specified conditions.
Derating
Operating a component below its maximum rating to improve reliability or account for heat, environment, or loading conditions.
Temperature Rise
The increase in temperature caused by current flow through a connector, wire, or component.
Contact Resistance
The electrical resistance at the contact interface of a connector or terminal.
Ampacity
The maximum current a wire or conductor can carry safely under specific conditions.
Creepage
The shortest path along an insulating surface between two conductive parts.
Clearance
The shortest air distance between two conductive parts.
Dielectric Strength
The ability of an insulating material to withstand voltage without breaking down.
Insulation Resistance
The resistance provided by insulation between conductive parts.
Power Supply
A device that provides electrical power to a circuit or system.
Busbar
A conductive metal bar used to distribute power, often in power panels, battery systems, or high-current equipment.
Signal & Data Terms
Signal
Electrical information carried through a circuit, wire, cable, or connector.
Signal Integrity
The quality of an electrical signal as it travels through a circuit, cable, or connector system.
Impedance
The opposition to alternating current or high-frequency signal flow, measured in ohms.
Impedance Matching
Designing a system so connected parts have compatible impedance, reducing reflections and signal loss.
Crosstalk
Unwanted signal coupling between nearby circuits, conductors, or connector contacts.
EMI
Electromagnetic interference. Unwanted electrical noise that can disturb electronic signals or equipment.
RFI
Radio frequency interference. Unwanted interference caused by radio-frequency energy.
Shielding
Conductive material used to reduce electromagnetic interference or protect signals.
Differential Pair
Two conductors carrying equal and opposite signals, commonly used for high-speed data transmission.
Bandwidth
The range of frequencies a system can carry or process effectively.
Frequency
The number of signal cycles per second, measured in hertz.
Attenuation
The reduction of signal strength as it travels through a cable, connector, or circuit.
High-Speed Connector
A connector designed to support fast digital signals while controlling impedance, crosstalk, and signal loss.
RF Connector
A connector designed for radio-frequency signals, commonly used with coaxial cable.
Testing & Compliance Terms
UL
Underwriters Laboratories. A safety certification organization commonly referenced for electrical products and components.
CSA
Canadian Standards Association. A standards and certification organization commonly used for products sold in Canada.
RoHS
A regulation that restricts certain hazardous substances in electrical and electronic equipment.
REACH
A European regulation related to the registration, evaluation, authorization, and restriction of chemicals.
IP Rating
Ingress protection rating. A rating that describes protection against dust and water intrusion.
NEMA Rating
A rating used for electrical enclosures to describe environmental protection levels.
Flammability Rating
A rating that describes how a material behaves when exposed to flame.
HiPot Test
A high-potential test used to check insulation strength and verify that parts can withstand specified voltage.
Pull Test
A test used to measure the mechanical strength of a crimp, wire termination, or connector retention feature.
Cycle Life
The number of mating and unmating cycles a connector is designed to withstand.
Insertion Force
The force required to mate a connector, insert a contact, or install a component.
Withdrawal Force
The force required to unmate a connector or remove a contact or component.
Agency Approval
Certification or recognition from a testing organization showing that a product meets certain standards.
Environmental Rating
A rating that describes how well a product can handle conditions such as moisture, dust, temperature, or vibration.
Manufacturing & Quality Terms
BOM
Bill of materials. A list of parts, components, and materials required to build a product.
AVL
Approved vendor list. A list of approved manufacturers or suppliers for a product or part.
MPN
Manufacturer part number. The official part number assigned by the manufacturer.
SKU
Stock keeping unit. A supplier or distributor’s internal product identification number.
Lead Time
The amount of time between placing an order and receiving the product.
MOQ
Minimum order quantity. The smallest quantity a supplier will sell or produce.
NCNR
Non-cancelable, non-returnable. An order condition where the buyer cannot cancel or return the product.
PCN
Product change notice. A notification that a manufacturer is changing a product, process, material, packaging, or manufacturing location.
PDN
Product discontinuation notice. A notification that a manufacturer plans to discontinue a product.
EOL
End of life. The point when a product is no longer being actively produced or supported by the manufacturer.
NRND
Not recommended for new designs. The part may still be available, but the manufacturer does not recommend using it in new products.
Obsolete
A product status indicating that a part is no longer actively manufactured or recommended for use.
Last Time Buy
The final opportunity to place an order before a product is discontinued.
Last Ship Date
The final date a manufacturer expects to ship a discontinued product.
Traceability
The ability to track a product or component through manufacturing, distribution, and usage history.
Lot Code
A code used to identify a specific manufacturing batch or production lot.
Date Code
A code that identifies when a product or component was manufactured.
Counterfeit Part
A part that is falsely represented as genuine, often creating quality, safety, or reliability risks.
Authorized Distributor
A distributor officially approved by the manufacturer to sell its products.
Gray Market
Product sold outside authorized distribution channels. It may be genuine, but traceability and warranty support can be limited.