Chrismukkah is a pop-culture portmanteau neologism referring to the merging of the holidays of Christianity's Christmas and Judaism's Hanukkah. It first arose in the German-speaking countries within middle-class Jews of the 19th century. After World War II, Chrismukkah became particularly popular in the United States, but is also celebrated in other countries.
The term was popularized beginning in December 2003 by the TV drama The O.C., wherein character Seth Cohen creates the holiday to signify his upbringing in an interfaith household with a Jewish father and Protestant mother. The holiday can also be adopted by all-Jewish households who celebrate Christmas as a secular holiday.