Related Clues:

• Apprehensive
• Stressed
• Past perfect, for one
• In need of a massage
• Knotted up
• Brace, in a way
• Present, e.g.
• It can be past or present
• On tenterhooks
• Drawn tight
• All wound up
• Ex-lax?
• Tightly stretched
• Grammarian's concern
• Stiffen