A speaker of the Basque language, or a person from the Basque Country.
From Euskera (the Basque language name, meaning 'Basque speaker') plus -dun (a suffix indicating 'one who speaks'). This term directly reflects the Basque language's own way of describing its speakers.
The Basque language is one of Europe's great linguistic mysteries—it's not related to any other European language, so words like 'eskualdun' preserve a naming tradition that stretches back thousands of years to people who lived in the Pyrenees before the Romans arrived.
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