periderm

noun

peri·​derm ˈper-ə-ˌdərm 

: an outer layer of tissue

especially : a cortical protective layer of many roots and stems that typically consists of phellem, phellogen, and phelloderm

Word History

Etymology

New Latin peridermis, from peri- + -dermis

First Known Use

1849, in the meaning defined above

Medical Definition

periderm

noun

peri·​derm ˈper-ə-ˌdərm 

: the outer layer of the epidermis of the skin especially of the embryo