When should you use a thesaurus?

Do you have one of those friends that you love to bits but whose every word should be taken with an enormous bag of salt? Well, that’s basically the relationship you should have with your thesaurus. Love it, but with caution.

Next time you reach for it, first ask yourself why. If it’s because you’re looking for a longer word in the hope of impressing your reader, stop right there. Readers judge writers who use simple language as more intelligent than those who needlessly pick long words, according to research by Professor Daniel Oppenheimer of Princeton University.

But the real danger of the thesaurus lies in the fact that each word it contains is out of context, and words don’t work well alone. Every word, however closely related to another it may be, has its own unique connotations: as David Crystal puts it, ‘[the thesaurus] contains no true synonyms’.

In his book Words Words Words, Crystal compares the apparent equals youngsters and youths, and asks: ‘Which group would worry you?’ And isn’t it true that you’d expect youngsters to be innocently playing in the park, while youths in hoodies skulk in the bushes?

And suppose a colleague was about to email you ‘I want to hold a meeting soon’, but then got thesaurus-happy and instead sent:

I ache to carry on a tryst lickety-split.

Well, that’s a harassment case waiting to happen, surely.

The best description of the thesaurus’s function comes from Professor Simeon Potter, a Fellow of the Royal Society of Literature and an Honorary Fellow of the Institute of Linguistics. He said of thesauri (yes, thesauri): ‘[they’re] a good reminder of words momentarily forgotten, but a bad guide to words previously unknown.’

If you know a word, you can recognise its suitability. If you take your old friend’s word for it, you could end up with a sentence that assumes a bizarre life of its own.

And, for anyone still doubting the dangers of thesaurus over-reliance, take a friendly tip and consider this case study.