What's the difference between Scrabble and its online equivalent, Scrabulous? Its developers, being sued by the game's makers, say it's that you can look up words. It might not be in the spirit of the game, but cheating has opened our eyes to some little known words.

Oolite. Sarodist. Psionic. Autopen. Avifauna. Graviton.

Come again? These words have all been deployed in Scrabulous games after being gleaned from a cheat site.

When faced with seven randomly picked letters and stuck for inspiration, reaching for a dictionary is frowned upon in the board game Scrabble (unless it's an unusually friendly bout). But in the online versions, it is impossible to know if your opponent is cheating.

"One of my friends takes me apart every time," says Shelley, a keen Scrabulous player. "She comes up with these bizarre words, yet she's not that intelligent. She cheats but she won't admit it. I cheat too, but say I don't."

Sarodist - someone who plays a sarod, a many-stringed lute from northern India - is Shelley's most recent cheat word, found on one of the many websites that show the highest scoring word to be made from any given letters.

Game of trust

"Scrabulous is essentially an open-book game," says Stewart Holden, of the Association of British Scrabble Players. "You just don't know if your opponent has used a word they know or if they have looked it up online. It's a bit of fun, so does it really matter?"

Scrabble champ Stewart Holden He adjudicates on another online version of Scrabble - the Internet Scrabble Club, which has also heard rumblings from Hasbro and Mattel's lawyers - and says that most complaints involve accusations of cheating.

"These are all just deleted. We don't have webcams on everyone's computer to tell if they are looking up words. If you don't like it, you can choose not to play that person again. You can either agree to play an open-book game or agree to trust that you each just go on your knowledge."

Martin, another Scrabulous zealot, says he's never discussed the use of electronic performance enhancement with his opponents, but has no problem with its occasional deployment.

"If they come up with a string of outlandish - and improbably high scoring - words, I'll probably resort to more computerised help, but as a matter of honour, I will try to use words I've heard of. I recently played 'oolite' - my opponent was a bit surprised but I did know it, a kind of limestone I'd come across in a sculpture class."

Anne Ramsay, also of the Association of British Scrabble Players, says it's easy to spot an opponent who is using a word finder or anagramer.

"The way that they play is totally different. They come up with wonderful seven, eight or nine letter words but miss the basic two or three letter words that would score much more highly. In one game my opponent put 'psionic' in a space at the bottom. I thought 'wow' but a few moves later they missed out on 'xi' for 52."

Does cheating in online Scrabble bother her? "No. I learned a new word."

Psionic is used in fiction and games to denote paranormal psychic abilities. And here are the definitions of the other words at the top of this article:

OOLITE - type of limestone
AUTOPEN - machine for automatically signing signatures
AVIFAUNA - birds
GRAVITON - hypothetical particle in physics.