ton-up boys

OEDがbikerの定義を改めるようです。The Telegraphによるとbikerの定義が、あまりに前時代的でステレオティピカルであるために、該当箇所である“a long-haired biker in dirty denims”という箇所を削除したとあります(Oxford Dictionary onlineの現在の定義は“a motorcyclist, especially one who is a member of a gang or group:a biker was involved in a collision with a car”)。

さて、赤字のton-up boyは、そんなbikerに関する表現でイングランド版bikerという感じ。意味は「スピード狂、走り屋、カミナリ族」などを意味します。特に1950年代1960年代のイングランドにおいてMods達と対立していたRockersを形容する言葉として使用されます(Modsについてはこちらを参照「No mod cons - 田邉祐司ゼミ 常時英心：言葉の森から」)。

また、ton-upのtonとはイングランドの俗語で「時速１００マイル(160km/h)」を意味します。(Othello)

Oxford English Dictionary drops 'dirty biker' definition - Telegraph

Oxford Dictionaries has dropped references to 'long hair' and 'dirty denims' in its definition of 'bikers' after motorcylists complained.

Oxford University Press, which publishes the Oxford English Dictionary, bowed to pressure from Britain's two-wheeled community, who claimed the description was outdated.

The online version previously defined biker as: "A motorcyclist, especially one who is a member of a gang: a long-haired biker in dirty denims."

However, figures show that far from the "long-haired and dirty denim" stereotype, fewer than one in 10 male bikers now has long hair (9 per cent).

Furthermore, almost half of British bikers (42 per cent) are totally free of tattoos, piercings, facial hair or gang markings.

(中略)

The bikers were described in the media in early 60s as "ton-up" boys.

Hannah Squirrell, from Bennetts, said: "In the early 60s, 'biker' was a relatively new term which provoked fear among many, partly due to their image portrayed in the media.