The state or characteristic of being without the sun or sunshine.(noun)
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Use "sunlessness" in a sentence
"This is one of the BBC's good old-fashioned dramas of flat caps and bicycles, cobbles and postal orders, as young James turns up in Scotland's capital of sunlessness with his cardboard suitcase and optimist's grin."
"The general belief seems to be that, in the end, it was the cold, damp, bleak sunlessness of Jura that did him in."
"A tendegree axial tilt, together with the orbit, means that the northern part of the Arctican continent spends half its year in unbroken sunlessness."