velamen

noun

ve·​la·​men və-ˈlā-mən 

plural velamina və-ˈla-mə-nə 

: the thick corky epidermis of aerial roots of an epiphytic orchid that absorbs water from the atmosphere

Word History

Etymology

short for New Latin vēlāmen rādicum, literally, "covering of the roots"; Latin vēlāmen "covering," from vēlāre "to cover, clothe" (verbal derivative of vēlum "awning, curtain") + -men, suffix of result — more at veil entry 1

First Known Use

1882, in the meaning defined above