Related Clues:

• 'Oh, why not?'
• Positive
• 'You betcha!'
• Answer to 'Shall we?'
• Irrefutable
• Positive reply to an invitation
• Cry of concurrence
• Permits
• Doesn't disallow
• Proven
• 'No problem!'
• 'Of course!'
• 'Let's do it!'
• Never-failing
• 'No sweat'