Related Clues:

• Interjection added to the O.E.D. in 2001
• Catchphrase introduced around the same time as 'don't have a cow, man'
• Homer Simpson word
• Spoken word that's a sound trademark of 20th Century Fox
• Classic catchphrase
• Blunderer's cry
• "How stupid of me!"
• Brow-slapper's syllable
• 'Simpsons' word added to the OED
• Dropped-donut reaction for Homer
• "Simpsons" word added to the OED
• 'Boy, am I an idiot!'
• Word with a head slap
• 'Who doesn't know that?!'
• Head-slapper's cry