Related Clues:

• See 40-Across
• Brief checkout lines?
• Cash bars?
• Merchandise ID
• Question answered by ''M'' or ''F''
• Type of symbol
• Cause of some R ratings
• Social rank
• Scandal subject
• Birth certificate info
• It's scanned in mkts.
• ID info
• It separates the girls from the boys
• Scanned bar
• Chromosome factor