Related Clues:

• 'Oh, that's it! (6)'
• One gets around like this
• 'O, that's 18 holes, of course (5)'
• 'O, that's it in 34 across (6)'
• Nothing could sound so naughty as this
• To get around the half-century it takes a sorceress
• Worthless sort
• Word with sewing or traffic
• O, that's it! Think nothing of it
• Loser's total in a shutout
• Half of 10?
• Human need
• Slimmer than slim
• Celsius freezing point of water
• Friends, metaphorically