Definition of what's with
1 : what is the reason for (something) (So) what's with the hat?
2 : what is wrong with (someone or something) What's with him? Is he upset?
Word by Word Definitions
: used as an interrogative expressing inquiry about the identity, nature, or value of an object or matter
: often used to ask for repetition of an utterance or part of an utterance not properly heard or understood
: in what respect : how
: used as an interrogative expressing inquiry about the identity, nature, or value of a person, object, or matter
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