Used to express extreme joy at something, it combines hooray, the Scots word yaldi and it is unnecessarily pluralised at the end for fun and to add substance to the word.
person 1: did you see the match last night
person 2: naw, I didnae, who won
person 1: (insert person 2's team here)
person 2: HOORALDIES!
person 2: naw, I didnae, who won
person 1: (insert person 2's team here)
person 2: HOORALDIES!
by Bobby Kryptonite January 13, 2011
Get the hooraldiesmug.