'Memorability' definitions:

Definition of 'memorability'

From: WordNet
noun
The quality of being worth remembering; "continuous change results in lack of memorability"; "true memorability of phrase"

Definition of 'Memorability'

From: GCIDE
  • Memorability \Mem`o*ra*bil"i*ty\, n. The quality or state of being memorable. [1913 Webster]