The term 'I Haven't the Foggiest' is an idiom that means to have NO IDEA or knowledge about something. The crossword solutions for this term are DUNNO (5 letters), GOTME (5 letters), and NOIDEA (6 letters). DUNNO is a slang term for 'I don't know', GOTME is a slang term for 'I got me', and NOIDEA is a combination of 'NO' and 'IDEA'. All three of these terms are used to express a lack of knowledge or understanding.