That would imply public domain. Every license has some licensing restrictions. MIT, BSD, and associated ones are closest to that, but still have restrictions. "Open source" in the literal sense in English is where the source is open to be looked at by everyone. Lots of software is like that, even fully commercial offerings. AGPL, GPL, and co have pretty drastic limitations on commercial usage (much more than the Commons Clause), but are obviously open source. The author should decide licensing, and if the source is available to be perused-- the English language would tend to call that, "open source". I think "OSI Approved Open Source License" would be a better phrase than the linguistically vague "open source". English has proper nouns for that sort of thing, and if we can go around writing "GNU/Linux", I think specifying the _type_ of open source license really isn't too much to ask for.
There are some licenses effectively like public domain, such as zero-clause BSD, CC0, WTFPL, Unlicense, etc.
GPL does not restrict commercial use any more than non-commercial use. What it does restrict is adding additional restrictions, it requires source code to be distributed, and it does not allow disallowing the user to substitute their own version.
If the source is available to be perused I think it is called "shared source" (or "source available"); "open source" is a subset of that, and is according to the OSI definition. "Free software" is also a subset of "source available". "OSI approved" is a subset of "open source" because OSI approved does not include public domain, even if it is still open source (which in some cases it is) (also some stuff that meets the OSI definition (by both words and intention) might not be OSI approved because OSI has not looked at it yet). And then there is also "FOSS".
That would imply public domain. Every license has some licensing restrictions. MIT, BSD, and associated ones are closest to that, but still have restrictions. "Open source" in the literal sense in English is where the source is open to be looked at by everyone. Lots of software is like that, even fully commercial offerings. AGPL, GPL, and co have pretty drastic limitations on commercial usage (much more than the Commons Clause), but are obviously open source. The author should decide licensing, and if the source is available to be perused-- the English language would tend to call that, "open source". I think "OSI Approved Open Source License" would be a better phrase than the linguistically vague "open source". English has proper nouns for that sort of thing, and if we can go around writing "GNU/Linux", I think specifying the _type_ of open source license really isn't too much to ask for.