The phrase "foggiest idea" means that someone doesn't have a clear understanding or knowledge about something. It suggests that their understanding is obscured or unclear, similar to a foggy weather condition. Full definition
His ambiguity is playful and insightful, not just a smokescreen for foggy ideas and visual notions. (filmcomment.com)
Every state has some sort of system in place to collect child support from a so - called «dead beat» parent, and these systems should be made use of instead of a custodial parent's foggy idea of justice. (divorcesource.com)
At Oakmark, we gladly buy attractively - priced stocks, even when we don't have the foggiest idea as to when they may trade at our estimate of intrinsic value. (oakmark.com)