Cool, didn't know that, but I can assure you it's also the name of a lake close to where I live

Make sure to always google a name you want to use before using it, to make sure you're not going to get clobbered by someone else's dominant SEO on the word.

Actually I did some very simple search and most results were about my local lake, so I figured that the context was different enough, we'll see.

That's personalized search results for you :) That lake would not be ranking high for anyone except the people in the vicinity.

Might search also using eu.startpage.com, Qwant, …and Kagi if you have it.

(( Tenno is also a Japanese word usually translated as "emperor". ))

This was my first thought, probably will make searching stuff difficult.

Should not be too bad. The two are different enough that you can add some sort of context to your search terms, like searching for "tenno markdown".

It’s also the Japanese Emperor.