Happy Whatever-Reason-It-Is-That-Im-Giving-You-This-Small-Insignificant-Piece-Of-Crap.

Must be said enthusiastically, and is simmilar to Happy Birthday, but for occasions when it may not be appropriate to say Happy Birthday, ie someones actuall birthday.
person, whilst handing someone somthig of little or no value: Happy Christmas
by cheeseflambe July 20, 2009
The alternative to merry christmas or happy holidays, only dipshits say this.
jerry: happy christmas
bob: merry christmas?
jerry: no i’m going to be an absolute shit and say happy christmas
by shittter6969 December 25, 2020
The royal family adopted "Happy Christmas" as their preferred greeting, and others took note (in fact, each year, Queen Elizabeth continued to wish her citizens a "Happy Christmas," rather than a merry one). But "Merry Christmas" has been used since at least 1534.
- Happy Christmas! - Queen Elizabeth (R.I.P.)
by frittatita December 25, 2022