Related Clues:

• It's nothing
• It precedes 15
• See 36-Across
• Nothing on the court
• Be gaga over
• Troubadour's subject
• Be wild about
• Romance
• Substance
• Everyone has one
• It means nothing to some people
• Zero, on a court
• Soul mate?
• It 'makes the world go round'
• Kind of language