Related Clues:

• 'Ahem' relative
• "Yoo-hoo!"
• 'What's the big idea?'
• 'Whoa there!'
• Cry to attract attention
• ''Watch where you're going!''
• 'I'm talkin' to you!'
• 'Watch it, mister!'
• Intrusion acknowledgment
• With 61-Down, Jimi Hendrix's first single ... or a hint to the starts of 20-, 28-, 45- and 50-Across
• ''Pay attention!''
• Attention-getting Pixies song?
• Train: "___ Soul Sister"
• What Outkast says before "Ya!"
• '98 Marvelous 3 "Album"