Knacker

A knacker /ˈnæk.ə(ɹ)/ is a person in the trade of rendering animals that have died on farms or are unfit for human consumption, such as horses that can no longer work. This leads to the slang expression "knackered" meaning very tired, or "ready for the knacker's yard", where old horses are slaughtered and the by-products are sent for rendering. A knacker's yard or knackery is different from a slaughterhouse, where animals are slaughtered for human consumption. In most countries, knackery premises are regulated by law.

A horse carcass, rendered, had many uses. In the U.S., the meat could be used as food at a mink ranch, pig farm, fox farm, or greyhound race track, in pet food, or in zoos. Bones were ground up for bone meal fertilizer. Hides were made into leather or, along with joints and hooves, processed to make glue for the furniture and book binding trades (hence the idea of old horses being sent to the glue factory).

In modern usage, especially in Ireland, the word has come to describe both those from lower-class backgrounds who tend to engage in anti-social behaviour, as well as those of an Irish Traveller background. In this sense, the usage of the word "knacker" is akin to the usage of the term "chav" in England and ned in Scotland. The variant term of 'Bulls Knacker' is prevalent in Newcastle upon Tyne, meaning someone who deliberately misbehaves.

The word "knacker" was first used in 1812. It is from the Scandinavian word represented by O.N. hnakkur saddle and hnakki "back of the neck".

The term is in this literal sense in British English and Irish English, and gained some notoriety during the outbreak of mad cow disease (BSE) in the United Kingdom. The Slaughterhouses Act 1974, the Meat (Sterilisation and Staining) Regulations 1982, and the Food Safety Act 1990 all define a "knacker's yard" as "any premises used in connection with the business of slaughtering, skinning or cutting up animals whose flesh is not intended for human consumption".

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