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Scientists are continually trying to count ever larger amounts and measure ever smaller quantities. And as they push the boundaries of counting further outwards and add still more zeroes to the end, they need names for their new numbers.

The standard approach to creating these is to add a prefix to an existing measurement word. So a kilometre is 1000 metres, and a nanosecond is a billionth of a second. The latest additions to the official list of prefixes were made in 1991. They were zetta-, which denotes a number followed by 21 noughts, and yotta-, 24 noughts.

You'd have thought those would be big enough for anyone, but now some scientists are saying they'd like a prefix for a number followed by 27 noughts – that's a thousand trillion trillion – and a student from the University of California has started a petition on Facebook to get hella- officially accepted for the job.

What are his chances of success? Not great. The people who adjudicate on these things like their prefixes to have a classical Latin or Greek origin. Hella- could hardly be less classical.

It's American students' slang for 'extremely'. So you might say 'It's hella cold today'. It probably comes from the phrase 'hell of a', referring to an extraordinary example of something.

But it's certainly expressive, and if the idea of a hellametre or a hellagram appeals to you, get on that petition and sign.

John Ayto is a lexicographer and a writer on words and language. He began his dictionary career as one of the editors of the first edition of the Longman Dictionary of Contemporary English, and over the past twenty years he has produced a range of his own books on the history and use of words, including the Bloomsbury Dictionary of Word Origins, the Oxford Dictionary of Modern Slang and Twentieth-Century Words, a survey of the new words that came into the English language during the twentieth century. He edited the 17th edition of Brewer's Dictionary of Phrase and Fable, and he has broadcast extensively on lexical matters.