'Unusualness' definitions:

Definition of 'unusualness'

From: WordNet
noun
Uncommonness by virtue of being unusual [ant: usualness]

Definition of 'Unusualness'

From: GCIDE
  • Unusual \Un*u"su*al\, a. Not usual; uncommon; rare; as, an unusual season; a person of unusual grace or erudition. -- {Un*u"su*al*ly}, adv. -- {Un*u"su*al*ness}, n. [1913 Webster]