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per·i·derm

(pĕrĭ-dûrm′)

The outer layers of tissue of woody roots and stems, consisting of the cork cambium and the tissues produced by it, such as cork.

per′i·dermal, per′i·dermic adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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