@Warsaw Wil: that's a very good point about the purpose and use of a dictionary, so please stop making valid points and leave me to my curmudgeonly prejudice.

I would have argued the case, but I just read that the Oxford Dictionary will now include 'OMG' - so I give up.

This whole conversation brings to mind one of my favourite sayings:

"Everyone is entitled to their own opinions, not everyone is entitled to their own facts"

Any word like LEGOES, LEGOS, LEGOs, or any attempt to pluralise the brand name LEGO is WRONG. It's grammatically wrong, and it's wrong according to the company who own the brand name.

In many circumstances there may be a social convention of dropping the noun and pluralising the brand name, such as BMWs or any other brna dname that does not actually name their product with the branded name. This convention, no matter how widely accepted and used, is not correct. It may have fallen into common useage, but it would not be used in any formal or official document where correctness of grammar is required, and is therefore WRONG.

So pluralise LEGO all you want, enjoy the sound of the word, let it roll off your tongue daily, just don't try to argue that it is grammatically correct,