An ethnonym, (in Greek ethnos: 'tribe', + onyma: 'name') is the name of an ethnic group. We speak of an exonym when the name has been attributed by another group, or of an autonomous one if it has been self-assigned. For example, the dominant ethnic group in Germany is that of the Germans, an exonym taken to Spanish from Latin; the Germans refer to themselves with the autonomous deutsch.
When a language evolves, ethnonyms that were once acceptable may become offensive. Examples of defamatory ethnonyms of history are cretino (gentilicio of Crete), vandal, barbarian, san, Phoenician, lapón, gringo, goyim, chichimeca, popoluca, payo and filisteo.
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