Related Clues:

• Looks inferior by comparison
• Shows fright
• Grows dim
• Reacts to a threat
• Tightens up
• Verb forms
• Blanches
• Steels
• Tightens, with 'up'
• Grammarian's concerns
• Gets taut
• Pickets outside a house?
• Reacts to a ghost, maybe
• Factors in conjugation
• Grammar class subjects