Hi Nox! I am so sorry to take so long to reply to this!
So it sounds like there are two problems. One is that there's no way to reliably pick random words with synonyms. That's a great idea, and I'll add it to the list.
The other is that it sounds like you're calling the Wordnik API from the client, and that's not a great idea for exactly the reason you state: it makes your key public, which is against our terms of service. We strongly require that you keep your key private. You can use a proxy server to do so -- there are a lot of good options, depending on what language and framework you use.
Good luck with your game!
Yours,
Erin
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Erin McKean
Wordnik
@emc...@xoxo.zone/@wor...@wordnik.social
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