FLOSS
= Free/Libre and Open Source Software
The concept combining both Free Software and Open Source Software seems most used in Europe because of its use by the EU.
It's similar to FOSS, Free Open Source Software, as well.
It has been suggested that the opposite of FLOSS is not "commercial software", since there are many commercial Open Source Software packages, but rather Software Manufacturing.
More Information
David Wheeler maintains a reference page on Free Software and Open Source Software.