At the most basic level, “Happy Christmahanukkwanzaa!” is just a fun, inclusive way to wish every one a happy holiday season without having to rely on that boring old “Happy Holidays!”
Christmahanukkwanzaa is the fusion of three major holidays of celebration and giving: Christmas, Hanukkah, and Kwanzaa. These three holidays are celebrated around the same time each year.
Christmahanukkwanzaa did not fuse the names of other holidays outside the three mentioned. However, no disrespect is intended here. In fact, all respect is intended to all people. The name was simply getting long already.