A phrase used when one does not know the answer to a question. Good question! I'll ask Marie to clarify that. Hmm, that's a good question—let me check my sources.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
ˌgood ˈquestion!(spoken) used to show that you do not know the answer to an important question: ‘How much is all this going to cost?’ ‘Good question!’
See also: good
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