Dangerous vs Lethal

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

Dangerous

Top 2,000 (common)A1adjective

Lethal

Top 5,000 (fairly common)C1adjective
Most common: Dangerous
 DangerousLethal
Pronunciation🇬🇧 /["/ˈdeɪndʒərəs/"]/🇺🇸 /["/ˈdeɪndʒərəs/"]/🇬🇧 /["/ˈliːθl/"]/🇺🇸 /["/ˈliːθl/"]/
Meaninglikely to cause harm or injurySomething that can cause death.
ExampleThe roller coaster is too dangerous for young children.She had been given a lethal dose of poison.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 5,000 (fairly common)
CEFR levelA1C1
Part of speechadjectiveadjective
Collocationsbe, feel, look, extremely, fairly, very, for, tobe, prove, absolutely, highly, potentially, to, be, prove, absolutely, highly, potentially, to
Antonymssafe, harmless, securesafe, harmless, non-lethal
Common mistakesUsing 'dangerous' when 'risk' or 'hazardous' is more accurate., Confusing 'dangerous' with 'endangered'., Using 'dengerous' as an adverb; it should only be an adjective.Confused with 'lethal' vs 'fatal'., Using it to describe non-dangerous situations., Incorrectly spelling it as 'leathal'.
Usage notesUse 'dangerous' to describe things that can cause harm. It's appropriate in most contexts, but be cautious in very casual situations where simpler words may work better.Use 'lethal' to describe something that can kill, like a weapon or poison. Avoid using it in casual conversations unless discussing serious topics.

Frequently asked questions: Dangerous vs Lethal

What's the difference between Dangerous and Lethal?

Dangerous: likely to cause harm or injury Lethal: Something that can cause death.

Which is more common: Dangerous and Lethal?

Dangerous is the most common in everyday English.

Which is more advanced: Dangerous and Lethal?

Lethal is the highest level, at C1, on the CEFR scale.

Are Dangerous and Lethal the same CEFR level?

Dangerous: A1, Lethal: C1 on the CEFR scale.

What part of speech are Dangerous and Lethal?

Dangerous: adjective, Lethal: adjective.

Can you show an example of each?

Dangerous: The roller coaster is too dangerous for young children. Lethal: She had been given a lethal dose of poison.

Can I use Dangerous and Lethal interchangeably?

Not always. Dangerous and Lethal 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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