Strange vs Unknown

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

Strange

Top 1,000 (very common)A2adjective

Unknown

Top 2,000 (common)B2adjective
Most common: Strange
 StrangeUnknown
Pronunciation🇬🇧 /["/streɪndʒ/"]/🇺🇸 /["/streɪndʒ/"]/🇬🇧 /["/ˌʌnˈnəʊn/"]/🇺🇸 /["/ˌʌnˈnəʊn/"]/
MeaningUnusual or odd; not normal.Not known or familiar.
ExampleThat was a strange noise coming from the basement.The mysterious book contained many unknown secrets.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelA2B2
Part of speechadjectiveadjective
Collocationsappear, be, feel, extremely, fairly, very, to, strange and wonderful, appear, be, feel, extremely, fairly, very, to, strange and wonderfulbe, remain, completely, entirely, quite, to, for parts unknown, to parts unknown, for reasons unknown, be, remain, completely, entirely, quite, to, for parts unknown, to parts unknown, for reasons unknown, be, remain, completely, entirely, quite, to, for parts unknown, to parts unknown, for reasons unknown
Antonymsnormal, usual, commonknown, familiar, certain
Common mistakesConfusing 'strange' with 'stranger', which refers to a person unknown to you., Using 'strange' when 'unusual' is more suitable in formal contexts., Overusing 'strange' when describing common things.Confused with 'unkown' — incorrect spelling., Using it in a sentence where something is actually known., Misplacing it in a sentence making it unclear.
Usage notesUse 'strange' to describe things that are not typical or expected. It can have a slightly negative connotation, depending on context, like feeling uncomfortable about something unfamiliar.Used to describe something that is not recognized or identified. Commonly used in everyday conversation and writing. Avoid when the context is clear without it.

See it in real clips

Strange
Unknown

Frequently asked questions: Strange vs Unknown

What's the difference between Strange and Unknown?

Strange: Unusual or odd; not normal. Unknown: Not known or familiar.

Which is more common: Strange and Unknown?

Strange is the most common in everyday English.

Which is more advanced: Strange and Unknown?

Unknown is the highest level, at B2, on the CEFR scale.

Are Strange and Unknown the same CEFR level?

Strange: A2, Unknown: B2 on the CEFR scale.

What part of speech are Strange and Unknown?

Strange: adjective, Unknown: adjective.

Can you show an example of each?

Strange: That was a strange noise coming from the basement. Unknown: The mysterious book contained many unknown secrets.

Can I use Strange and Unknown interchangeably?

Not always. Strange and Unknown 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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