I would like a term that is inclusive of CC0.
[1] https://creativecommons.org/faq/#can-i-apply-a-creative-comm...
> Also, the CC0 Public Domain Dedication is GPL-compatible and acceptable for software. For details, see the relevant CC0 FAQ entry.
(I also consider anything that fits the Open Source Definition to be "open source" and differentiate things actually approved by the OSI as "OSI certified", which should in principle be a subset of "open source".)