Octoberfest vs Oktoberfest

Octoberfest and Oktoberfest both are nouns.

Word	Noun	Adjective	Verb	Adverb
Octoberfest	Yes	No	No	No
Oktoberfest	Yes	No	No	No

As nouns, Octoberfest and Oktoberfest are synonyms defined as:

Octoberfest and Oktoberfest: a strong lager made originally in Germany for the Oktoberfest celebration; sweet and copper-colored

Octoberfest (noun)	Oktoberfest (noun)
a strong lager made originally in Germany for the Oktoberfest celebration; sweet and copper-colored	an autumn festival that involves merrymaking and drinking beer
	a strong lager made originally in Germany for the Oktoberfest celebration; sweet and copper-colored