A sleeveless undershirt or vest, especially one worn in Scottish and Northern English dialects.
Possibly from Guernsey, the Channel Island, where similar knitted garments were made. The word may derive from 'Guernsey' contracted and altered over time as the garment became common in working-class communities.
Ganzies were the original 'performance wear' for British laborers and fishermen—the fine knit could stretch and move with the body while keeping warmth, making it perfect for hard physical work.
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