Cool MateDeadly vs Lethal
When to use each in English, with meaning, register, and examples.
Deadly
Top 2,000 (common)B2adjective
Lethal
Top 5,000 (fairly common)C1adjective
Most common: Deadly
| Deadly | Lethal | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈdedli/"]/🇺🇸 /["/ˈdedli/"]/ | 🇬🇧 /["/ˈliːθl/"]/🇺🇸 /["/ˈliːθl/"]/ |
| Meaning | causing or capable of causing death | Something that can cause death. |
| Example | The snake's venom is deadly and can cause severe symptoms within minutes. | She had been given a lethal dose of poison. |
| Register | Neutral | Neutral |
| How common | Top 2,000 (common) | Top 5,000 (fairly common) |
| CEFR level | B2 | C1 |
| Part of speech | adjective | adjective |
| Collocations | deadly weapon, deadly poison, deadly disease, deadly force, deadly smile | be, prove, absolutely, highly, potentially, to, be, prove, absolutely, highly, potentially, to |
| Antonyms | harmless, safe, non-lethal | safe, harmless, non-lethal |
| Common mistakes | Confusing 'deadly' with 'deathly' which has a different meaning., Using 'deadly' when describing something non-lethal like a game or competition. | Confused with 'lethal' vs 'fatal'., Using it to describe non-dangerous situations., Incorrectly spelling it as 'leathal'. |
| Usage notes | Use 'deadly' to describe things that can kill, like diseases or poisons. Avoid using it casually; it sounds serious and should not be used for light situations. | Use 'lethal' to describe something that can kill, like a weapon or poison. Avoid using it in casual conversations unless discussing serious topics. |
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Frequently asked questions: Deadly vs Lethal
What's the difference between Deadly and Lethal?
Deadly: causing or capable of causing death Lethal: Something that can cause death.
Which is more common: Deadly and Lethal?
Deadly is the most common in everyday English.
Which is more advanced: Deadly and Lethal?
Lethal is the highest level, at C1, on the CEFR scale.
Are Deadly and Lethal the same CEFR level?
Deadly: B2, Lethal: C1 on the CEFR scale.
What part of speech are Deadly and Lethal?
Deadly: adjective, Lethal: adjective.
Can you show an example of each?
Deadly: The snake's venom is deadly and can cause severe symptoms within minutes. Lethal: She had been given a lethal dose of poison.
Can I use Deadly and Lethal interchangeably?
Not always. Deadly 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.