good question!

good question

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.
See also: good, question
Farlex Dictionary of Idioms.

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
Farlex Partner Idioms Dictionary
See also:
  • be (just) good friends
  • be good friends
  • do no good
  • (one) (has) never had it so good
  • (it's) good to be here
  • for good measure
  • be as good as new
  • do (one) a/the world of good
  • as good as it gets
  • (as) good as new
References in periodicals archive
In "Now That's a Good Question! How to Promote Cognitive Rigor Through Classroom Questioning", author and educator Erik M.
Now That's a Good Question!
Now That's a Good Question!: How to Promote Cognitive Rigor Through Classroom Questioning
Now That's a Good Question!: How to Promote Cognitive Rigor Through Classroom Questioning
An eco-minded client once asked me, "Why would I choose to buy acreage?" Good question! land has intrinsic value," I answered.
Land: a green investment
ANOTHER GOOD QUESTION! THE ARMY BEGAN PUTTING ACUS IN THE CLOTHING BAG IN FY 06.
Don't be faked out *
Good question! Editors love discussing fine distinctions.
Blond thinking