ˌeksōˈdərmə̇s noun
( -es )
Etymology: New Latin, from exo- + -dermis
1. : a layer of the outer living cortical cells that by becoming cutinized or suberized takes over the functions of the epidermis in roots such as those of the monocotyledons and some dicotyledons which lack secondary thickening
2. : the single layer of cells just below the corky epidermis of various orchid roots