Nuin is a Basque surname from the province of Navarre in Spain, and has the same origin as the word noain. The original meaning of the name is not known, with the only suggested theory by Narbarte who contends that it relates to the word, Munogain, which means the 'higher part of a hill'.
There are Nuin families in:
- Biscay: Bilbao, Galdakano.
- Guipúzcoa: Arrasate, Donostia.
- Navarre: Arbarzuza, Aizoain, Arribe, Astrain, Auza, Beriain, Doneztebe, Iruna, Lizarra-Estella, Olite, Orokieta, Tafalla, Zizur In 1350 was an NYUYN family documented.
The suffix AIN is typical in the surnames of Navarre, probably meaning "place of", although another possibility for the meaning is NUNOAIN-NOAIN or NUNUIN-NOIAN or NOIN, the change of OA in U is usual in Basque.