Used in the late Old English period, the word night meant “the dark part of a day; the night as a unit of time; darkness,” also “absence of spiritual illumination, moral darkness, ignorance”. Written niht (West Saxon neath, Anglian naeth, neht), the noun came from Proto-Germanic languages. This one word is from the Proto-Indo-European and is after the verbal root *neg- “to be dark, be night.” In Old English combinations, night was “the night before (a certain day or feast day). To work nights preserves the Old English genitive of time. Night soil “excrement”, from the 1770s, is so called…