The state or characteristic of being without the sun or sunshine.
1999, Tim Radford, "Light and shade," Guardian (UK), 7 Aug. (retrieved 3 Aug. 2009):In Penzance and Falmouth, the total eclipse will last for 2 minutes 2 seconds. The longest period of sunlessness will be in Romania, at 2 mins 23 seconds.
1882, George MacDonald, Weighed and Wanting, ch. 7:The honor she paid the honesty of these women helped her much to pity the sunlessness of their existence, and the poor end for which they lived.
1986, Terrence Anthony Whalen, Philip Larkin and English Poetry, UBC Press, ISBN 9780774802321, p. 116:Given such an aware sensibility, they move, it seems to me, marginally past the sunlessness of a great deal of the wasteland literature of this century, and past the literature of despair of our own day.
