It’s actually a hebrew word.  It means “dedication”.  But, as they say, ask three Jews a question and you’ll get four opinions, or, in this case, 17.

We did some sluething and found, on yumshugar.com of all places, a quiz that spelled them all out:

Chanuccah, Channuka, Channukah, Chanuka, Chanukkah, Chanuko, Hannuka, Hannukah, Hanuka, Hanukkah, Hanukka, Hannukka, Kanukkah, Khannuka, Khannukah, Khanukkah, Khanukkah.

Not sure what the qualifications are for one spelling being “correct” and another not, but there you go.  Happy early Khannukkah!