dyad /dīˈad/

1. A pair of units treated as one
2. A bivalent atom, radical, or element (chem)

dyadˈic adjective

• piteousnesses
• pitfall
• pitfalls
• pith
• pithball
• pithballs
• pithead
• pitheads
• Pithecanthropus
• pithecoid
• pithed
• pithful
• pith hat
• pith hats
• pith helmet
• pith helmets
• pithier
• pithiest
• pithily
• pithiness
• pithinesses
• pithing
• pithless
• pithlike
• pithoi