Related Clues:

• Sharpen an axe blade
• Sharpen, like a skill
• Sharpen (with a whetstone)
• Sharpen, like an appetite
• Fine-tune over time
• Perfect gradually
• Sharpen, like skills
• Improve through practice
• Sharpen, as an axe
• Put an edge on a blade
• Stir grain, removing article
• Make sharper, as a knife edge
• Sharpen, as a sword's edge
• Take a strop to