The BBC's Peter Hunt boldly goes ...

Oxford University Press says the rule of not splitting infinitives is based on a fallacy.

They blame its accepted use on the failure of traditionalists to understand English grammar.

What grammatical traditionalists will make of it

The rule itself is based on Latin, where verbs consist of only one word.

The infinitive, therefore is never split.

The dictionary explains: "the dislike of split infinitives eg 'to boldly go where no man has gone before' is long-standing but ... not well founded, being based on an analogy with Latin.

"In Latin, infinitives consist of only one word (eg. crescere `to grow'; amare `to love'), which makes them impossible to split: therefore, so the argument goes, they should not be split in English either."

Billed as the most important new English dictionary this century, is published on Thursday.

Blairite is now an official word

The edition took 30 editors and 60 worldwide consultants six years and £3m to complete.

It contains more than two thousand new words, including Blairite, alcopop and tamagotchi.

The Oxford University Press started from scratch to redefine every word in the language.

The result contains 350,000 words, but fewer meanings for individual words than previous dictionaries.

That is because, using new psychological theories on how our brains use language,the dictionary identifies a small number of core meanings for each word.

Dictionary was started from scratch - and included Instants

As well as the new words and phrases - such as Instants, off message and road rage - the dictionary also gives advice on political correctness.

Tips on word usage includes how saying black, white, or person of colour is acceptable - but spinster, squaw and harelip is not.

The dictionary is the first written from scratch by the Oxford University Press in more than 70 years.

The latest computer technology was used to analyse how the meaning of words have changed.

Oxford University Press spokeswoman Helen McManners said: "We started compiling it six years ago. It was an absolutely monumental task."

Tamagotchi makes it into the book

Using written English in novels, reference books, magazines, newspapers and transcripts of the spoken word a 'corpus evidence' was created so every word in the language could be analysed for its different meanings.

Each time a word occurs it was fed into a database along with a 'tag' defining its meaning in that context so when a lexicographer defined it they could call up the ways it is used in the corpus evidence.

Ms McManners said: "What this means is that 20 years worth of reading can be scanned in seconds to see exactly how that word is used and what it means."