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

• signally
• signalman
• signalmen
• signal peptide
• signals
• signal sequence
• signal-to-noise ratio
• signal-to-noise ratios
• signaries
• signary
• signatories
• signatory
• signature
• signatures
• signature tune
• signature tunes
• sign away
• signboard
• signboards
• signed
• signer
• signers
• signet
• signeted
• signeting