Sex, Slang, and Pejorative (or at Least Formerly Pejorative) Ethnic Stereotypes:
Which terms referring to particular sexual practices derive from the names of particular ethnicities or nationalities? Two should be pretty obvious (one can be even a single word, while the other seems to be in the dictionary only using the nationality's name plus a noun), but the source of one other word struck me as quite surprising when I first learned about it. An interesting perspective, it seems to me, on how these terms develop, often stemming from political and religious animosities that are now long forgotten.
Rules for answers: Please quote or link to a dictionary (including a slang dictionary) that supports your definition and, where the etymology is at all controversial, the etymology.