periderm /perˈi-dûrm/

1. The horny cuticular covering of a hydroid colony
2. The cork cambium with the cork and other tissues derived from it, forming a protective outer covering in plants

peridermˈal adjective

• tripiest
• tripinnate
• Tripitaka
• Tripitakas
• triplane
• triplanes
• triple
• Triple Alliance
• triple bill
• triple bogey
• triple bond
• triple bonds
• triple crown
• triple-crowned
• triple crowns
• tripled
• Triple Entente
• triple event
• triple events
• triple glazing
• triple harp
• triple harps
• triple-headed
• triple jump
• triple-jump