Yes.
Depending on which plan you’re on, you have an allotment of separate WordPress instances which can all have different CNAMEs, databases, and installations. You are free to divide those up and use those however you choose (i.e. dev/staging/test/production).
The Performance plan, for example, allots you 35 WordPress installs. The Performance+ plan offers up to 60 apps. Find a complete breakdown of our plans and the different resources applied in our Plan Matrix Table.