When a person is waiting for someone, which one would be the correct to use/grammatically correct? - "Who are you waiting for?" OR "Whom are you waiting for?"
Who are you waiting for?

Extremely formal:
For whom are you waiting?
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Thank you AlpeccaStars.
How about: For who are you waiting?
Perfect StrangerHow about: For who are you waiting?
That is sometimes said by those who are trying to be more formal but do not know how to do so. AS's two sentences are the correct informal and formal variations; this last one is a mongrel. Either front the preposition and use the formal object pronoun, or use the subject pronoun and leave the preposition to dangle.
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