You have a mobile site that uses separate URLs. That is in the same category as m-dot sites, but your site doesn't use a mobile subdomain, it uses a mobile subdirectory.
From Google's mobile SEO overview, the three types of mobile designs are:
- Responsive Web Design
- Dynamic Serving
- Separate URLs
/mobile/ subdirectory puts your site in the "Separate URLs" category. Because an m-dot website is also "Separate URLs", any m-dot advice is likely going to apply to your website as well.
The reason that Google calls the category "separate URLs" and says "sometimes known as m-dot" is because there are other ways to make separate URLs other than a
m. mobile subdomain. In your case you have a subdirectory. It is possible to use URL parameters like
?mobile=true. You could use a different subdomain such as
phones.example.com instead of
m.example.com. In any case, all the m-dot advice applies to you and I would recommend using the term "separate URLs site" rather than "m-dot site".