This surname Zammuto is of Italian origin. The meanings and origins of Italian surname: Zammuto however is unexplained. Perhaps a variant of Italian: Gammuto.
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Gammuto is an Italian surname. It originated in the village of Longobucco, which is in the Province of Cosenza.
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Another possible origin is that perhaps Zammuto is a variant of Basque: Zamudio.
Zamudio - Basque: habitational name from Zamudio in Biscay province, so named from Basque zame 'ravine' + dio 'terrain with water'.