Nightsides

Part of speech: noun

Definitions

1. The aspects or qualities of the night that are often mysterious or hidden from view
2. The darker, less understood parts or sides of a situation or phenomenon that are only revealed in the nighttime
3. Aspects of life or nature that are associated with darkness and nighttime, often implying secrecy or the unknown

Etymology: "Nightsides" is the plural of "nightside", a noun formed by simply placing "night" and "side" together. The compound is transparent: the night-side is the side of something that faces away from the sun and lies in darkness, and its plural extends that sense to several such aspects at once. The planetary sense is the literal origin. A planet's nightside is the hemisphere turned away from its sun, so the word began as a description of physical geography before it was turned toward the metaphorical. From there it came to name the darker, hidden or unfamiliar parts of life, which is how the plural is most often used today.