Meaning & use
insulator
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Meanings
nouncountablephysics
A material that does not let electricity pass through it easily, such as rubber or plastic.
Grammar: Countable: a good insulator, several insulators.
Patterns
- an insulator against something
- a good insulator of something
Rubber is a good insulator, so electricians wear rubber gloves.
Glass insulators hold the power lines away from the metal poles.
Dry wood is a poor insulator when it gets wet.
nouncountable
A material that slows the loss or gain of heat or the passage of sound, such as foam, fiberglass, or wool.
Grammar: Often followed by against or of: an insulator against cold.
Patterns
- an insulator against cold
- an insulator of sound
Thick snow acts as an insulator and keeps the ground warm.
The foam board is a cheap insulator for attic walls.
A layer of fat is a natural insulator for seals.
nouncountablefigurative
A person or thing that shields someone from harsh or unpleasant outside influences.
Grammar: A figurative use: an insulator from criticism.
Patterns
- an insulator from something
Her wealthy family acted as an insulator from the worst of the recession.
A strong savings account can be an insulator against sudden bills.
Word forms
| plural | insulators |
|---|
Common combinations
- electrical insulator
- Plastic coating makes the wire an electrical insulator on the outside.
- thermal insulator
- Wool is an excellent thermal insulator.
- good insulator
- Air trapped in feathers makes down a good insulator.
- poor insulator
- Metal is a poor insulator of heat.
- acoustic insulator
- Heavy curtains work as an acoustic insulator.
Synonyms and how they differ
- nonconductor
- Nonconductor is a plain technical word for a substance that does not carry heat or electricity, while insulator also names the use of the material.
- lagging
- Lagging is the British word for material wrapped around pipes to keep heat in, and it is narrower than insulator.
- dielectric
- Dielectric is a specialist term for an insulating material in electric fields, such as in capacitors.
- buffer
- Buffer is a general word for anything that softens an impact, without the technical meaning of insulator.
Opposites
Word family
- insulate verb
- to cover or protect with insulating material
- insulation noun
- the material or process of insulating
- insulating adjective
- serving to stop heat, electricity, or sound passing
- insulated adjective
- covered or protected with insulation
- superinsulator noun
- a material with extremely high resistance, studied in physics
Commonly confused: insulator or isolator? insulator or conductor?
insulator vs isolator
An isolator is a device that cuts a part of an electrical circuit off, while an insulator is a material that blocks the flow.
insulator vs conductor
A conductor is the opposite: a material that lets electricity or heat pass easily.
Practice
Which material is a good electrical insulator?
Choose one answer.
Rubber does not conduct electricity easily, so it insulates. Copper, steel, and aluminum are metals that conduct electricity well.
Make it your own
Write a sentence using “insulator”, then check it and compare it with the examples above.