yötön
Yötön is a Finnish adjective meaning “without night” or “nightless.” It is formed from the noun yö “night” with the negative suffix –tön, comparable to the English suffix –less. In everyday language yötön describes a condition in which darkness does not occur, most commonly referring to the phenomenon of the midnight sun experienced above the Arctic Circle during summer months. In this context the phrase yötön yö “nightless night” is used to denote the period when the sun remains visible for 24 hours.
The term also appears in Finnish literature, music and film, often as a metaphor for continuous illumination,
Geographically, yötön conditions are observed in Finnish Lapland, particularly in municipalities such as Rovaniemi and Inari,
In contemporary usage yötön also functions metaphorically in media headlines and advertising to suggest perpetual activity,