After using the Wikipedia app for a few days I decided to use instead the Merriam Webster app with the Define button in Word 2013. I was able to make that work, but the Wikipedia app is still installed even though it's hidden in my MS account.
In addition, there is a Wikipedia icon in the Apps group on the Insert menu. I also noticed that I can click on that icon and it functions whether I am logged into my MS account or not. This is different behavior from the other apps I've tried.
How does one uninstall the Wikipedia app and remove its icon from Word 2013?