1. pronoun /wɔt,ʍɒt,wɒt,wʌt,ʍʌt/
a) which thing, event, circumstance, etc.: used interrogatively in asking for the specification of an identity, quantity, quality, etc.
What is your address?
b) An interrogative which asks "Dont you agree?"
You told them what?
2. adverb /wɔt,ʍɒt,wɒt,wʌt,ʍʌt/
a) in some manner or degree; in part; partly; usually followed by with.
What with singing and joking, the time passed quickly.
b) Such; this is; that is.
What a pity.
3. interjection /wɔt,ʍɒt,wɒt,wʌt,ʍʌt/
a) an expression of surprise or disbelief.
What! That’s amazing.
b) is that not true?
It’s a nice day, what? (sometimes repeated, e.g.: What-what?)
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