Related Clues:

• Lack discretion
• Blab freely
• Hootenanny, e.g.
• Let the air out?
• Belt, perhaps
• Melodize
• Croon a tune
• Attempt a number
• Reveal a secret
• Belt it out
• Tell just about anybody
• Tell on
• Give the game away
• Ruin the secret
• Talk, in a way