Old English beneoðan "beneath, under, below," from be- "by" + neoðan "below," originally "from below," from Proto-Germanic *niþar "lower, farther down, down" (see nether). Meaning "unworthy of" is attested from 1849 (purists prefer below in this sense). "The be- gave or emphasized the notion of 'where,' excluding that of 'whence' pertaining to the simple niðan" [OED].