Gas vs Vapor

When to use each in English, with meaning, register, and examples.

Gas

Top 1,000 (very common)A2noun

Vapor

Top 2,000 (common)B1noun
Most common: Gas
 GasVapor
Pronunciation🇬🇧 /["/ɡæs/"]/🇺🇸 /["/ɡæs/"]/🇬🇧 //ˈveɪpə//🇺🇸 //ˈveɪpər//
MeaningA substance that is neither solid nor liquid, such as air.A gas or mist that comes from a liquid.
ExampleThe gas in the balloon made it float high in the sky.The vapor from the boiling pot filled the kitchen.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelA2B1
Part of speechnounnoun
Collocationsdeadly, noxious, poisonous, emit, give off, produce, build up, leak, emissions, chamber, butane, coal, natural, cook with, light, turn on, appliance, boiler, central heating, gas mark 2, 3, etc., pedal, stationwater vapor, vapor pressure, vapor trail, vaporization process
Antonymssolid, liquidsolid, liquid
Common mistakesConfused with 'gasoline' when referring specifically to fuel., Using 'gases' as a singular form., Mixing up with 'gaslight' which means to manipulate someone's perception.Confusing with 'steam' which is specifically from boiling water., Using 'vapor' for solid substances instead of gases.
Usage notesUsed in everyday conversation to refer to fuel, but can also refer to air or vapor. In a scientific context, it can denote a state of matter. Avoid in very formal writing.Use 'vapor' in scientific contexts or when discussing weather. Avoid informal settings.

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Gas

Frequently asked questions: Gas vs Vapor

What's the difference between Gas and Vapor?

Gas: A substance that is neither solid nor liquid, such as air. Vapor: A gas or mist that comes from a liquid.

Which is more common: Gas and Vapor?

Gas is the most common in everyday English.

Which is more advanced: Gas and Vapor?

Vapor is the highest level, at B1, on the CEFR scale.

Are Gas and Vapor the same CEFR level?

Gas: A2, Vapor: B1 on the CEFR scale.

What part of speech are Gas and Vapor?

Gas: noun, Vapor: noun.

Can you show an example of each?

Gas: The gas in the balloon made it float high in the sky. Vapor: The vapor from the boiling pot filled the kitchen.

Can I use Gas and Vapor interchangeably?

Not always. Gas and Vapor are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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