https://wordalist.com/blog/delete-account/
Don't want to hang around anymore? We're sorry to see you go, but to unlearn what you've learned, login to your account and go to Settings / Remove account (or follow this link: http://wordalist.com/user/edit/remove-account)
Note:
Once you've unlearned, for eternity your knowledge will be lost. If you change your mind, start from beginning you must, young padawan.