Best definition
1: multiple “yays!!”
2: a more enthusiastic way of saying “yay!!”A: if a guy says it they are possibly gay.
Person 1: “Oh MY Gawd, here, let me give you a hug!!!”

Person 2: “Yaysies!!”
yaysies: define #2
When you hear some great news and use the word Yay with an extension of excitement.
Yaysies} my word has finally made it to the Urban Dictionary!