Related Clues:

• Eight, as a prefix
• Prefix for "eight"
• Hedron intro
• Two times tetra-
• Tetra- + tetra-
• 81-Across, as a prefix
• Prefix with "gon"
• Valence lead-in
• Prefix with "dexterous"
• Dextrous beginning
• Two-thirds of dodeca-
• Prefix meaning "both"
• Prefix with -dextrous
• Prefix before hedron or gon
• Both: Pref