This is one that came up:

https://wordnet.princeton.edu/

I saw do this was also participating in some kind of ESL education regarding synonyms, which is essential to this plagiarism technique.

I actually thought it might be something like this at first but I don't think so.

and doom Steemit to be no more than a platform for AI rewards mining, at the expense of actual people.

too late... :D

I am hoping that the coming AI will be counteracted with another AI and we can witness the destruction of the world because of copy paste.