Related Clues:

• The "O" in CD-ROM
• '___ You' (1955 Platters hit)
• "I'm __ human"
• With 5-Across, barely
• Start of an excuse
• Start of an objection
• "___ in America"
• Restricted to
• Just no coming back to river in Cork reportedly
• "I'm ___ human"
• On the sly, Seth leaves to exclusion of everything else
• Lacking siblings
• At best, it's not off the river in Cork reportedly
• With 'in' and 12-Down, as a precaution
• ''This is __ a test''