Slang is essential in any living, growing language; some slang words lose their vulgar stigma and pass into respectable usage. But because slang is also a fashion, it means that many serviceable words and subtle shades of meaning can be lost.

Take, for example, some English Edwardian slang terms for ill-behaved men — bounder, rotter, stinker and cad, all of which could be intensified in stages with the qualifiers fearful, frightful and absolute. These originated in the speech of students at the universities of Oxford and Cambridge in the 1880s, migrated into smart London speech before World War I and were still in common use in the 1950s.

A cad — or perhaps a stinker — receives his comeuppance

Their passing, along with other subtly graduated terms of opprobrium, has deprived us of an important set of social nuances.

The bounder was a crass, uneducated, contradictory sort of fellow quite unaware of the dislike of others and of the irritation caused by his loud and over-confident tone and behaviour; a bounder was often nouveau-riche and an energetic gate-crasher.

The rotter displayed most of the characteristics of the bounder but added to it a jeering sense of humour perceptible only to himself; to rot something, such as a friend’s new car, clothes or girlfriend, was to criticise loudly and usually ignorantly.

The stinker had elements of both bounder and rotter, but added greed and indifference to the comfort and patience of others. The rotter might cast aspersions on the character and appearance of your girlfriend — but the stinker would do his best to steal her with as debonair a mien as he would guzzle the last three inches of your last bottle of Napoleon brandy.

The cad displayed none of the more egregious characteristics of the bounder and the rotter, but like the stinker he would not only try to steal your girlfriend but actually succeed in doing so, only to cast her carelessly aside when he spotted his next victim.

And among artists, a crude, vulgar or overly sentimental painting dashed off as a speedy pot-boiler was known as a cad-catcher.

It was the misfortune of the Edwardian bus conductor to also be known as a cad, but it is likely that everyone understood the difference.