Related Clues:

• 'Heck if I know'
• ''I'm at a loss''
• Pronounced as 'venson'? I haven't a clue!
• '???'
• "I'm clueless"
• 'Got me'
• "Darned if I know"
• 'Darned if I know'
• 'Couldn't tell ya!'
• ''I'm flummoxed''
• "I haven't the foggiest"
• Empty-headed remark?
• 'I'm drawing a blank'
• "I'm drawing a blank"
• 'Haven't the foggiest!'