Yeah where does it become a violation. Like if i wrote an app called wordsmith, and it does basically what word does, let you edit documents, is that really a trademark violation? Because i used the word word?

Considering Microsoft wasn't allowed to use SkyDrive as a name for cloud storage because Sky is registered for unrelated purposes, I would assume using the same trademark in a directly competing product would not be allowed.

https://www.geekwire.com/2013/microsoft-rename-skydrive-sett...