Lunatic vs This one is a fuckin' madman

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

Lunatic

InformalBeyond 10,000 (less common)C2noun

This one is a fuckin' madman

SlangTop 2,000 (common)
Most formal: LunaticMost common: This one is a fuckin' madman
 LunaticThis one is a fuckin' madman
Pronunciation🇬🇧 //ˈluː.nə.tɪk//🇺🇸 //ˈluː.nə.tɪk//🇬🇧 //ðɪs wʌn ɪz ə ˈfʌkɪn ˈmædmæn//🇺🇸 //ðɪs wʌn ɪz ə ˈfʌkɪn ˈmædmæn//
MeaningA person who is crazy or behaves very strangely.This person is very crazy or wild.
ExampleThe scientist was called a lunatic for his bizarre theories.Did you see how he drove? This one is a fuckin' madman!
RegisterInformalSlang
How commonBeyond 10,000 (less common)Top 2,000 (common)
CEFR levelC2-
Part of speechnoun
Collocationscrazy lunatic, dangerous lunatic, mad lunatictotal madman, acting like a madman, madman in the street
Antonymssane, rational, reasonable-
Common mistakesUsing 'lunatic' to describe someone without mental illness., Confusing with 'maniac', which has a slightly different meaning., Overusing in serious contexts where a more respectful term is appropriate.Confusing 'madman' with 'madwoman' when referring to a female., Using 'fuckin' in formal contexts, where profanity is inappropriate., Translating directly into other languages without considering slang usage.
Usage notesOften used in a derogatory way to describe someone perceived as irrational or mentally unstable. Be cautious of context; using 'lunatic' may offend some.Used informally, often among friends or in casual conversations. May not be appropriate in formal settings or with unfamiliar audiences.

See it in real clips

Lunatic
This one is a fuckin' madman

Frequently asked questions: Lunatic vs This one is a fuckin' madman

What's the difference between Lunatic and This one is a fuckin' madman?

Lunatic: A person who is crazy or behaves very strangely. This one is a fuckin' madman: This person is very crazy or wild.

Which is more formal: Lunatic and This one is a fuckin' madman?

Lunatic is the most formal of these.

Which is more common: Lunatic and This one is a fuckin' madman?

This one is a fuckin' madman is the most common in everyday English.

Can you show an example of each?

Lunatic: The scientist was called a lunatic for his bizarre theories. This one is a fuckin' madman: Did you see how he drove? This one is a fuckin' madman!

Can I use Lunatic and This one is a fuckin' madman interchangeably?

Not always. Lunatic and This one is a fuckin' madman 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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