Why was "tantrum" trending last week?
1580s as a type of knitted cloth; 1842 as a breed of cattle; both from Jersey, one of the Channel Islands. Its name is said to be a corruption of Latin Caesarea, the Roman name for the island (or another near it), influenced by Old English ey "island;" but perhaps rather a Viking name (perhaps meaning "Geirr's island"). The meaning "woolen knitted close-fitting tunic," especially one worn during sporting events, is from 1836.
outer garment, usually knitted or crocheted, that is worn on the upper part of the body, either pulled over the head or buttoned down the front or back. Although hand knitting of wool had been practiced for about 2,000 years, it was not until the 15th century that the first knitted shirts or tunics were produced on the English Channel islands of Guernsey and Jersey; hence the English name jersey. The knitted garments were made by the wives of fishermen and sailors from natural wool, which, by retaining its oil, protected against the cold even when damp. The use of the jersey spread throughout Europe, especially among workingmen. In the 1890s it was adopted by athletes in the United States and called a sweater.