'Solitariness' definitions:

Definition of 'solitariness'

(from WordNet)
noun
The state of being alone in solitary isolation [syn: loneliness, solitariness]
noun
A disposition toward being alone [syn: aloneness, loneliness, lonesomeness, solitariness]

Definition of 'Solitariness'

From: GCIDE
  • Solitariness \Sol"i*ta*ri*ness\, n. Condition of being solitary. [1913 Webster]