Other forms: foggiest; foggily; foggier
Something that's foggy is cloudy or murky, filled with fog. A foggy view is blurred and indistinct, just like a foggy mind.
Driving on a foggy road can be tricky, since it's more or less like driving inside a cloud. When the inside of your head feels this way — blurry, clouded, and vague — you can also used foggy in a figurative way: "Her memory grew foggy as the years went by." Experts aren't sure whether foggy or fog came first, but in either case they suspect a Scandinavian root.