"A very hot and spicy curry", Probably from Portuguese vin d'alho 'wine and garlic (sauce)', from vinho 'wine' + alho 'garlic'.
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The vindaloo is one of the hottest curries in the British Indian restaurant's repertoire, but in origin the word was not Indian and did not imply spiciness. It probably derives from Portuguese vin d'alho ‘wine and garlic sauce’. A recipe for vindaloo is recorded in English in 1888, which describes it as a Portuguese curry, but it did not become familiar until Indian restaurants spread widely in the 1960s.[vindaloo etymology, vindaloo origin, 英语词源]