The mPoints is available only on the free app; it's not available on the premium app or with the Removes Ads upgrade. You can contact mPoints at email@example.com to make sure that the points you accumulated is still saved. As long as you've been signed in to Dictionary.com using your mPOINTS account then all of those points will remain in your mPOINTS account despite deleting or reinstalling specific apps. You may also find the information you need here.
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