Related Clues:

• Get one to advance to the next round without playing an opponent
• Informal farewell or thank you
• Have a double of this before you go
• This extra is no greeting if it comes at the double
• One might go and say this at the double
• 19 down with thanks
• Thanks to its being such a good buy, by the sound of it
• At the double at parting
• It's said to be good at parting for 22 down
• That sounds like a good buy, deserving gratitude at the double
• Such extra may come at the double on parting
• Fare well with such an extra double
• "Sayonara!"
• It renders a seed inactive
• Conversation stopper