Related Clues:

• Such extra may come at the double on parting
• Fare well with such an extra double
• Both extra at parting
• 'When one is going to be fair and well, by the sound of it (3-3)'
• "Sayonara!"
• 'Ciao for now!'
• It renders a seed inactive
• Conversation stopper
• Doubly thankful to hear this as one leaves?
• Exit line
• 'g2g' follower
• "Bon voyage!"
• Nicer "Good riddance"
• Famous last word?
• 15 means extra repeats