What is the meaning of the "-osic" suffix on a metal (e.g., cobaltosic oxide)?

I just came across the term *cobaltosic* for the first time in the abstract of [*Ind Eng Chem Res* **52**(18): 6076, 2013](http://dx.doi.org/10.1021/ie4003766) (emphasis added):



> 
> A nanocomposite of ***cobaltosic oxide*** and nitrogen-doped graphene ($\ce{Co3O4}$/N-G) was prepared by the facile hydrothermal method. 
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> 


I assume this is a historical name; Wikipedia's article on the [cobalt spinel](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiBiN7tj6LKAhUDox4KHbqaBpMQFggeMAA&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FCobalt(II%2CIII)_oxide&usg=AFQjCNHPaDx2R_v8UHxb-JgLrQo5AL8l7A&sig2=yQHo8witCG-0I76E01a4kA) mentions *cobaltosic oxide* as an "other name", but provides no other historical information. Google searches on [manganosic oxide](https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=manganosic%20oxide&nfpr=1) and [ferrosic oxide](https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=ferrosic%20oxide&nfpr=1) turn up the sort of results I would expect, though not all consistent:


*Manganese*


* Analogous to cobalt, manganosic oxide appears to be the $\ce{Mn3O4}$ spinel; e.g., see the abstract [here](http://nvlpubs.nist.gov/nistpubs/jres/041/6/V41.N06.A04.pdf) (PDF at link).


*Iron*


* The term *ferrosic* appears to refer (at least) to a mixed-oxidation state hydroxide, $\ce{Fe3(OH)8}$; e.g., [here](https://books.google.com/books?id=AbHflCKg5YkC&pg=PA46&lpg=PA46&dq=ferrosic%20oxide&source=bl&ots=leSphpZaGD&sig=KkyDiens31DStNlmHlKfkiuFn00&hl=en&sa=X&ved=0ahUKEwiA5ri2kaLKAhUF_R4KHTozDngQ6AEIHjAA#v=onepage&q=ferrosic%20oxide&f=false).
* However, it is also used to refer to the iron $\ce{Fe3O4}$ spinel (magnetite); e.g., [here](http://www.naturalpigments.com/natural-black-oxide.html).


What is the meaning of this "*-osic*" suffix?




In the course of searching for examples of usage of the "*-osic*" suffix, I think I found the answer to my own question. From the [last link](http://www.naturalpigments.com/natural-black-oxide.html) in the question, a web store selling pigments (emphasis added):



> 
> The source of natural black oxide usually is from an iron ore called magnetite. ***Magnetite***, also known as lodestone, is a ***ferrous ferric oxide (ferrosic oxide)*** that is a heavy, black color and opaque. 
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So, it would appear that the suffix indicates a compound of mixed oxidation state: a combination of -**o**u**s** and -**ic** forms of the metal.


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