Cool MateDeadly vs Fatal vs Lethal
When to use each in English, with meaning, register, and examples.
Deadly
Fatal
Lethal
| Deadly | Fatal | Lethal | |
|---|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈdedli/"]/🇺🇸 /["/ˈdedli/"]/ | 🇬🇧 /["/ˈfeɪtl/"]/🇺🇸 /["/ˈfeɪtl/"]/ | 🇬🇧 /["/ˈliːθl/"]/🇺🇸 /["/ˈliːθl/"]/ |
| Meaning | causing or capable of causing death | causing death or serious injury | Something that can cause death. |
| Example | The snake's venom is deadly and can cause severe symptoms within minutes. | The disease was fatal and claimed many lives before a cure was found. | She had been given a lethal dose of poison. |
| Register | Neutral | Neutral | Neutral |
| How common | Top 2,000 (common) | Top 2,000 (common) | Top 5,000 (fairly common) |
| CEFR level | B2 | C1 | C1 |
| Part of speech | adjective | adjective | adjective |
| Collocations | deadly weapon, deadly poison, deadly disease, deadly force, deadly smile | be, prove, nearly, always, invariably, for, to, be, prove, absolutely, ultimately, to | be, prove, absolutely, highly, potentially, to, be, prove, absolutely, highly, potentially, to |
| Antonyms | harmless, safe, non-lethal | harmless, safe | 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 'fetal', which relates to unborn babies., Misuse in non-life-threatening contexts, like 'fatal' for minor injuries. | 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 'fatal' when referring to something that can cause death or is very dangerous. Avoid using it in casual conversations unless it's serious. | Use 'lethal' to describe something that can kill, like a weapon or poison. Avoid using it in casual conversations unless discussing serious topics. |
See it in real clips
Frequently asked questions: Deadly vs Fatal vs Lethal
What's the difference between Deadly, Fatal, and Lethal?
Deadly: causing or capable of causing death Fatal: causing death or serious injury Lethal: Something that can cause death.
Are Deadly, Fatal, and Lethal the same CEFR level?
Deadly: B2, Fatal: C1, Lethal: C1 on the CEFR scale.
What part of speech are Deadly, Fatal, and Lethal?
Deadly: adjective, Fatal: adjective, Lethal: adjective.
Can you show an example of each?
Deadly: The snake's venom is deadly and can cause severe symptoms within minutes. Fatal: The disease was fatal and claimed many lives before a cure was found. Lethal: She had been given a lethal dose of poison.
Can I use Deadly, Fatal, and Lethal interchangeably?
Not always. Deadly, Fatal, 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.