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Compare French merveille (“wonder; marvel”).
mèrvelle f (plural mèrvelles)
- (Jersey) wonder
1903, Edgar MacCulloch, “Proverbs, Weather Sayings, etc.”, in Guernsey Folk Lore[1], page 533:Quand i' plleut ôve vent d'amont, ch'est merveille si tout ne fond.- When it rains with an east wind, it is a wonder that everything does not melt.