Related Clues:

• Sex lead-in?
• Athlete's outfit, briefly
• One before bi
• Tri- less two
• Prefix with brow
• Form intro
• Lateral or cycle lead-in
• Single starter
• One, for openers
• Lateral beginning
• Both: Pref.
• Inclusive prefix
• Verse opening
• "Mono" cousin
• Prefix with valent