Definition
An electrical component designed to oppose, or resist, the flow of current in a circuit. Resistors are used to limit current, drop voltage to a desired level, or divide voltage between parts of a circuit. Their opposition to current is measured in ohms.
Plain English
A small part in an electrical circuit that pushes back against the flow of electricity, slowing it down to a controlled amount.
Context Anchor
Seen in aircraft electrical system descriptions, wiring diagrams, instrument circuits, and troubleshooting discussions.
Derivation
From the Latin resistere, meaning 'to stand back' or 'to oppose.' A resistor literally stands against the flow of electrical current.
Why Pilots Care
Proper resistors protect sensitive avionics from excess current, prevent overheating, and support reliable operation of lights, instruments, and charging systems.
Analogy
Think of a resistor like a narrow section in a garden hose. Water still flows through, but less of it gets past, and the pressure drops on the far side.
Intuition Check
A resistor does not usually stop electricity completely. It limits or controls the flow of electricity in a circuit.
Example Sentence 1
A resistor in the panel lighting circuit limits current so the bulbs glow at the correct brightness.
Example Sentence 2
During an electrical check the technician measured the resistor to confirm it was still limiting current correctly.