An ethnonym (from the Greek: ἔθνος éthnos 'nation' and ὄνομα ónoma 'name') is a name applied to a given ethnic group. Ethnonyms can be divided into two categories: exonyms (whose name of the ethnic group has been created by another group of people) and autonyms, or endonyms (whose name is created and used by the ethnic group itself).

As an example, the ethnically dominant group in Germany is the Germans. The ethnonym Germans is a Latin-derived exonym used in the English language. Conversely, the Germans call themselves the Deutsche, an endonym. The German people are identified by a variety of exonyms across Europe, such as Allemands (French), tedeschi (Italian), tyskar (Swedish) and Niemcy (Polish).

As a sub-field of anthroponymy, the study of ethnonyms is called ethnonymy or ethnonymics.

Ethnonyms should not be confused with demonyms, distinctive terms that designate all people related to a specific territory, regardless of any ethnic, religious, linguistic or some other distinctions that may exist within the population of that territory.[1]