Epidermis

Epidermis could refer to:

1. In plants, the outermost layer of cells covering the leaves and young parts of a plant is the epidermis.
2. In vertebrates, epidermis is the outermost layer of the skin.
3. In invertebrates, the outermost layer of cells of the organism.

Etymology: 17th Century, via Late Latin from Greek, from epi- (upon) and derma (skin)