Real Dictionary

epidermis
a sensory nerve ending that changes specific stimuli into nerve impulses [...]
a small simple room, as in a prison, convent, or monastery; cubicle [...]
an element or cause that contributes to a result [...]
the process or act of growing, esp in organisms following assimilation of food [...]
the thin protective outer layer of the skin, composed of stratified epithelial tissue [...]
singular noun: Your epidermis is the thin, protective, outer layer of your skin.

epidermis in American English
the outermost layer of the skin in vertebrates, having no blood vessels and consisting of several layers of cells, covering the dermis
noun: the outer, nonvascular, nonsensitive layer of the skin, covering the true skin or corium

epidermis in British English
noun: the thin protective outer layer of the skin, composed of stratified epithelial tissue