No. "Free Software" is a term created by RMS/FSF. "Open Source" was later "formalized" by OSI to differentiate.

FSF puts it this way:

> Another group uses the term “open source” to mean something close (but not identical) to “free software.” We prefer the term “free software” because, once you have heard that it refers to freedom rather than price, it calls to mind freedom. The word “open” never refers to freedom.

https://www.gnu.org/philosophy/free-sw.en.html

The OSI has its definition here: https://opensource.org/osd

And yes, the term "open source" predates OSI, but till OSI didn't have any specific definition and was slightly different for everybody. OSI created a mostly accepted definition whoch is distinct from FSF's Free Software definition.