Definition from Wiktionary, the free dictionary
yay + -ness
- (slang, childish) yay; hooray
- 2000, "Miss Sparkle", Much yayness of the yay variety! (on Internet newsgroup alt.uk.penpals)
- Wooo, yayness for you also! :)
- 2001, "Belegdel", ten for ten [poll] (on Internet newsgroup aus.culture.gothic)
- I finally have Aliens Special Edition! Yayness!