https://www.uspto.gov/trademarks/search/likelihood-confusion
> Trademarks don’t have to be identical to be confusingly similar. Instead, they could just be similar in sound, appearance, or meaning, or could create a similar commercial impression. Here are examples of trademarks that were found to be confusingly similar.
> These trademarks are confusingly similar because they could be pronounced the same way, even though they’re spelled differently.
> Your mark -- T. Markey
> Conflicting mark -- Tee Marquee
Trademark conflicts in open store sometimes start that way. For example, “CouchBase” was a reference to “CouchDB” — it was originally a complementary effort, but later became a competitor. By the time the CouchDB folks realized that they should’ve been enforcing their trademark, it was too late.