Meaning & use
poison gas
Last updated
Meanings
noununcountable
A gas that harms or kills people who breathe it, sometimes released deliberately as a weapon.
Grammar: Usually uncountable, so no plural: 'the use of poison gas'; a specific type can be counted, as in 'a poison gas'.
Patterns
- release poison gas
- use poison gas against someone
- be killed by poison gas
The soldiers put on masks when they heard that poison gas had been released.
International law bans the use of poison gas in war.
Rescue teams warned that poison gas might still be leaking from the damaged factory.
nouncountabletechnical
A particular toxic gas, such as chlorine or sarin, that can be used to attack people.
Grammar: Countable when you mean one specific substance: 'a poison gas', 'several poison gases'.
Patterns
- a poison gas
- develop poison gases
Chlorine is a poison gas that attacks the lungs.
Chemists worked on ways to detect poison gases on the battlefield.
Common combinations
- release poison gas
- The report said the army had released poison gas over the village.
- poison gas attack
- Hundreds of people were hurt in the poison gas attack.
- a cloud of poison gas
- A cloud of poison gas drifted slowly toward the town.
- ban poison gas
- Many countries signed a treaty to ban poison gas.
- poison gas mask
- Every soldier was given a poison gas mask.
Synonyms and how they differ
- toxic gas
- A neutral, scientific term for any harmful gas; use it in technical writing, while 'poison gas' often suggests deliberate use as a weapon.
- chemical weapon
- A wider term covering poison gas as well as liquids and other chemicals used to harm people in war.
- nerve gas
- Names one especially deadly family of poison gases that attack the nervous system.
Word family
Commonly confused: poison gas or gas?
poison gas vs gas
'Gas' alone is a general word for any gas, including cooking fuel; 'poison gas' is specifically a harmful one used to attack people.
Practice
Which sentence uses 'poison gas' correctly?
Choose one answer.
'Poison gas' as a weapon is uncountable, so it takes no plural and no article here. The other options add impossible plural or article forms.
Make it your own
Write a sentence using “poison gas”, then check it and compare it with the examples above.