Related Clues:

• Grew rigid (with ''up'')
• Made tight, as muscles
• Became taut
• Prepared for trouble
• Prepared for a blow
• Prepared for a shock
• Showed anxiety
• Was uptight
• Became rigid
• Reinforced
• Prepared, as for a jolt
• Tightened (up)
• Supported, as framework
• Tightened
• Steadied against a blow or shock