What's the difference between "Mediary" and "Intermediary"?

Question

I can't find a definition for Mediary, I thought they kind of mean the same thing. But how they each precisely defined? And can someone use a good example of both? Thanks

Answer 1

It has got to be a "word" though used in specific domains, in very formal writing. In all citations below, emphasis has been added on purpose.

Paul Cobley, Ed., Routledge companion to semiotics and linguistics, 1963, p.33

Thirdness can be tentatively qualified as that which brings about mediation between two other happenings in such a manner that they interrelate with each other in the same way they interrelate with the third happening as a result of its mediary role. … Due to the mediary role of thirdness, each of the categories can intermittently play the role of any of the other categories.

Appears like the word is used in a similar sense to intermediary with a subtle difference. esp., in academic writing, in the fields of computer science (information mediary), biology (bio-mediary), law, commerce (service mediary) and philosophy. A large number of such instances can be found online (Books, ~15k; Web ~117k).

Abrahamson JA, et al., on pubmed:

Lay information mediaries (LIMs) seek information on behalf or because of others, without necessarily being asked to do so or engaging in follow up, and have represented more than 50% of health information seekers in prior studies.

MJ Robson explains:

What is a Mediary?
… The word Mediary has no dictionary definition, nor does it have any common usages. Inter-Mediary has a definition. Like other compound words, such as Inter-National, Inter-Denominational, or Inter-Species, it seemed to me that the second half of Inter-Mediary should stand as a word in its own right.
Well, it doesn’t.
It HAS been used by others, mostly in the digital information world, usually referring to a ‘portal, or aggregation’ model like Travelocity.com. A middle man, with or without a distinction. So, some very smart people have tried to use Mediary as an adjective or and adverb, but never as a Noun.

COCA has at least two entries for the word:

• Kent Nelson, Who Is Danny Pendergast? 2011
• Geoff Ryman in 'Fantasy & Science Fiction,' 117 3/4; p.105, 2009

Answer 2

There is no English word "mediary", as the word "intermediary" is a borrowing from the French. The closest word in English to "mediary" is "mediator", and both Mediator and intermediary have nearly identical meanings, a third person who acts in negotiations between two other parties.