An impostor is a person who deceives others by pretending to be someone else.
You can also come across another form of this word: imposter.
The pronunciation of the word is /ɪmˈpɑːstɚ/.
There are lots of synonyms that mean more or less the same, like for example: fake, faker, fraud, hoaxer or pretender, to mention just a few.
And here are some examples where this word is used:
The man who claimed to be a police officer turned out to be an impostor.
We all thought she was an impostor, but she really was the princess she said she was.
He said he was your friend, boss. That’s why I let the impostor in.
This impostor was really smart. Nobody recognized him.
They sent an impostor to infiltrate our company.
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