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SOME RANTS AND RAVES FROM A VERY SILVER SURFER
Both the Oxford Australian Dictionary and the Oxford New Zealand Dictionary say the origin of 'tinny' is the earlier slang of tin for money. This is known from 1836. The Oxford English Dictionary notes, “Said to have been first applied to the small silver coins of the 18th century, which before their recall in 1817 were often worn quite smooth without trace of any device, so as to resemble pieces of tin.” Part of the stimulus for inventing it may have been the even older brass for money, which is known from the sixteenth century.
The Bulletin of Sydney noted in 1898 that a tin back is “a party who’s remarkable for luck”. Much later, tin-arsed appears as a term for a person who is remarkably lucky. This has puzzled some writers, who don’t see the historical link with the money sense of tin, and have suggested it means somebody who is well protected in the fundament by a metal sheet so a kick there doesn’t cause any pain. The variant tin bum is known in New Zealand.
Who cares - I won. Interestingly I also entered Christine but again it was me who won.
A couple of other competitions are around but I haven't got the time to go if I win.
What a tough life!