got me stumped

you've/it's got me stumped

slang I don't know; I have no idea. Well, you've got me stumped. When did Millard Fillmore become president? Can you help me with this math problem? It's got me stumped.
See also: stump

(You've) got me stumped.

Inf. I can't possibly figure out the answer to your question. Bill: How long is the Amazon River? Jane: You've got me stumped. Bob: Do you know of a book that would interest a retired sea captain? Sally: You've got me stumped.
See also: stump