What is the name of a mix between Shih Tzu and Chihuahua?

There isn't a specific, officially recognized name for a mix between a Shih Tzu and a Chihuahua. However, there are a few common names used for this hybrid breed:

* Shih Tzu-Chihuahua mix - This is the most straightforward and accurate way to describe the breed.

* Chih Tzu - A combination of the two parent breeds' names.

* Chi-Shi - Another shortened combination of the names.

It's important to remember that these are just informal names, and there are no official breed standards or registries for mixed breeds.