Related Clues:

• Like proverbial hen's teeth
• Expected, as a baby
• Short of medium
• Hardly seen
• Hardly well done
• Owed, as a debt
• Like inverted Jenny stamps
• Almost unique
• Undercooked
• On the pink side
• Owing (to)
• Tough to catch
• Deserving of success
• Ready to have a baby
• "___, medium or well-done?"