EVER SINCE THE SMOKING BAN in enclosed public places came into force last July, there has been a marked upsurge in smirting, proving that the great British public can adapt and adopt new words in the most unlikely circumstances. Smirting happens when two people, smoking outside, fall to flirting, and discover that they have more in common than simply nicotine. In Ireland, where the term originated after the ban in 2004, there is even evidence of non-smokers joining the smoky throng outside because the atmosphere there is more flirtatious.

Perhaps the sense of sharing a semi-illicit activity adds to the sexual frisson. Rain even seems to encourage smirting, since smokers must huddle closer together.

Smirting is a portmanteau word, formed by packing parts of two words together to create another, combining the sense of each. Smirting is a first cousin of smog (smoke + fog). The notion of a portmanteau word is comparatively new. In Lewis Carroll's Through the Looking Glass (1871), Humpty Dumpty explains to Alice: “‘slithy' means ‘lithe and slimy'...You see it's like a portmanteau - there are two meanings packed up into one word”; later the doomed egg adds: “‘Mimsy' is 'flimsy and miserable' (there's another portmanteau...for you)”.

A portmanteau was a suitcase that hinged in the middle like a book, allowing one to carry clothes in one side and anything else in the other. The word is itself a portmanteau, formed by combining porter, the French for to carry, with manteau, meaning coat, cloak or mantle.

Before Carroll, the offspring of word marriages were rare, yet a number sneaked into the language anyway: dumbfound, a combination of dumb and confound, and twirl, a portmanteau of twist and swirl. In 1896, Punch invented “brunch”, combining breakfast and lunch.

Yet today the portmanteau is probably the most fertile vehicle for neologisms. Entire countries have been formed by packing two place names together: Tanzania, for example, was formed in 1964, linguistically speaking, by combining Tanganyika and Zanzibar. Many people seem to regard “Oxbridge” as a place, rather than an idea.

This is only a guesstimate (guess + estimate), but the internet (international + network) has produced thousands of new portmanteau words: blog (web and log), webinar (a web-based seminar), wikipedia and so on.

Portmanteau words offer excellent opportunities for insults. “Celebutard” is a rare blend of three words, celebrity, debutant and retard, and more or less precisely describes Paris Hilton. “Bliar” was a fortuitous combination that did incalculable damage to Tony Blair.

Combining the names in a famous couple can be a way of implying that they are a brand, indistinguishable as individuals: Billary (Bill and Hillary Clinton); Brangelina (Brad Pitt and Angelina Jolie). Some marrying couples, to avoid the social connotations of double-barrelling or to retain nominal independence, combine their names into a portmanteau: Miss Smith and Mr Jones became Mr and Mrs Smones or, less melodiously, the Jiths.

This trend began on May 18, 1992, in New York, when Valerie Silverman married Michael Flaherty and became Mr and Mrs Flaherman. The combined surname solution would not work for everyone. If, say, I had married someone with the name Baldwin, then we might have ended up as the Baldtyres. Imagine if Mr Dickens married Miss Whitehead. Whitens is not a particularly attractive surname, but it is a lot better than the alternative.

The Watergate affair gave birth to the laziest and longest-running family of blend words, not so much portmanteaux as identical cheap matching luggage. The suffix -gate is routinely attached as journalistic shorthand to anything that might be even vaguely scandalous. Squidgygate, Monicagate, Whitewatergate and Nipplegate - Janet Jackson's celebrated self-exposure at the 2004 Super Bowl, which may be the stupidest gate-word ever coined but which left us with a handy and lasting euphemism in the form of “wardrobe malfunction”.

The best portmanteaux are those that reflect a new way of thinking and behaving. “Viagravation”, for example, meaning “problems caused in a relationship by altered sexual expectations” and “sacrilicious”, which precisely captures the pleasure of being rude about someone else's religious beliefs, and was coined by that master-etymologist, Homer Simpson.

The term smirting fulfils this requirement, but the new habit, and accompanying new word, may not end there. Because senior executives now have to smoke outside along with everyone else, they apparently get to know the other smokers in the office better than non-smoking workers, and are thus more likely to promote them. Smoking may be bad for your health, but it might be good for your career. What is the correct term for this new social interaction? Smokomotion? Increasing your cancearning potential? Working nicovertime? Being a brownlung?

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