To the non-specialist, dictionaries are the source of authoritative judgements; I’m allowed to use a word because it’s in the dictionary; I know how to spell it and what it means because the dictionary tells me; I can settle an argument or win some points at Scrabble by appealing to the dictionary. So I know that regolith means ‘solid material covering bedrock’ because the Oxford English Dictionary (OED) tells me so. The dictionary is like judges handing down decisions about each word of the language – wise people interpreting the rules of the language for particular cases. The purpose of the dictionary is to lay down the law, to tell you what you must or mustn’t say.

The language specialist usually sees dictionaries as neutral descriptions of what people say and write. The OED aims to include every English word that has been used since 1150AD. It tries to establish what each word meant in its original context and gives you the quotations that attest silly meant something like ‘unsophisticated’ when applied to people up till the eighteenth century. Recent dictionaries try to record the words that people are using today: if i-pod or hammered then they must be there – chav is still not in the on-line OED for example. The purpose of a dictionary is to record what people say, not to tell them what not to say. It’s more like mapping the human genome than advocating eugenics.

Suppose then you come across the word advisory as a noun and don’t know what it means. In most cases of course you can guess from the context – that is after all how we learn the meanings for most words while children. Or you go to a dictionary and discover it means bulletin in the USA. This is perhaps the ideal use of a dictionary, par excellence in translation dictionaries because you’re less likely to know a word in a second language.

Or someone tells you the word you’ve said is not a word, say humungus. You look it up in the dictionary and it’s not there. Oh dear you’re ashamed and won’t use it again. Of course this may simply be due to the dictionary’s ignorance rather than yours. All dictionaries are based on limited information about English compared to the immense amounts spoken and written every day. Listen to a person talking constantly on a mobile at a rate of say 200 words a minute – 12000 an hour. Think of a teacher talking for say five hours a day - 60000 words, 300000 a week, say 12 million a year. Now multiply by the number of mobile users, the number of teachers or indeed the number of people in England. Or the people that speak English as native speakers, say 350 million, or the number of people who use English in the world, at last a billion. Despite trying to take in every word that’s said, the amount of English a dictionary can look at is a minute fraction of that spoken or written in a day. The seven Harry Potter novels are something like 1.5 million words long, the written output of just one person. So any dictionary is obviously going to miss something, perhaps your word happens to be local to your environment and not visible to the dictionary-makers – say folly in the sense of alleyway for the inhabitants of Colchester or chare for the same for those who live in Newcastle. But that’s their problem, not yours.

New words come into the language all the time, say shockumentary or blog; the lead time between the dictionary makers finding the word in a text and publishing the dictionary can be considerable. So it’s hard to ever say that your word is wrong; it may not have been recorded in the dictionary’s sample or be more recent. The practical problem is simply that people may not follow you if they don’t know the word, not that it breaches some rule.

The debate between the specialist and the non-specialist flared up notoriously with the publication of the infamous Third edition of Webster’s Dictionary in 1961. People were shocked that the dictionary was resigning its role as judge over the English language by including words such as ain’t; linguists were amazed at the wrong impression the public had of their role.

This is not to say that it is inconceivable that the dictionary should ever lay down the law about words. Dr Johnson aimed in his dictionary to ‘preserve the purity and ascertain (make certain) the meaning of our English idiom’; the very fact that the meaning of ascertain has so changed show he didn’t succeed. Yes the French academy has tried to lay down the permissible words in French, say ordinateur rather than computer. But it’s rather like King Canute showing you can’t control the tide; you may catch a few words but you don’t have any influence over the sheer flood rolling in continuously.

Most modern English dictionaries like the Longman Dictionary of Contemporary English are based on a definite corpus of English – a collection of sentences amassed from as wide and representative range of sources as possible. EG Their justification is that they tell you what words are being used today and what they mean, a kind of opinion poll of words, rather than simply reflect the judgments and opinions of the dictionary maker. Like opinion polls, they neutrally provide the data on which other people can decide what should happen if they want.  Of course dictionaries have to sell themselves to purchasers. Every year dictionary publishers parade this season’s fashionable accessory. One makes a fuss of the new words that have had to be added, another of its new enormous data-base – in actual fact this is just the dictionary makers doing their normal job. Another highlights its new system of including bad spellings to help bad spellers; perhaps a useful little trick but most people nowadays probably don’t need a dictionary for this, just a spelling checker. In other words dictionary makers have to balance their core scientific duty against their need to sell books – dictionaries are vast moneyspinners.

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