not have the faintest idea/notion
1 of 2phrase (1)
: to not know at all
He didn't have the faintest idea/notion what she was talking about.
not have the faintest/slightest idea
2 of 2phrase (2)
: to not know or understand at all
I don't have the faintest/slightest idea what you're talking about.
Cite this Entry
“Not have the faintest idea/notion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/not%20have%20the%20faintest%20idea%2Fnotion. Accessed 17 Jun. 2026.
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Merriam-Webster unabridged
