For once I’ll advocate that our community uses rather the “european” word FLOSS than anything else used around.
- OS is for me rather Operating System (and thus confusing)
- OSS is rather Operating System Support for Telco providers, and also a french spy as well
- FOSS is the name of a company: http://www.foss.com/ so my willingness to fight with trademark related stuff is weak here !
So remains FLOSS: Free/Libre Open Source Software/Solutions. Maybe longer but much less ambiguous. And contains clearly the notion of liberty we’re all attached to.