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baño m. (Noun) "bath"
11th cent. From Vulgar Latin baneum 'id.,' from Latin balneum - a syncopated variant of the more conservative balineum - borrowed from Greek βαλανεῖον (balaneîon) "bath," "bathing room." A Pre-Greek substrate word.
Found as the name of the village of Baño in Galicia. In the feminine, found in the village name La Baña, used throughout Leon and Galicia. In the plural it is a common toponym throughout Spain, dating back to the public bath houses of Roman times. Also the origin of the Valencian surname Buñol and the Navarran surname Buñuel.
Indo-European
Romance
Asturian bañu, Portuguese banho, Galician baño, Catalan bany, French bain, Italian bagno, Romanian baie

"For a term for bathing in warm water, which is probably an Aegaean custom, we might expect a Pre-Greek origin." ~ Robert S. P. Beekes (2014).