The Collaborative International Dictionary of English v.0.48:

Gayness \Gay"ness\, n.
   Gayety; finery. [R.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

gayness
    n 1: a sexual attraction to (or sexual relations with) persons
         of the same sex [syn: homosexuality, homosexualism,
         homoeroticism, queerness, gayness]