Wikipedia
Inter se (also styled as inter sese) is a Legal Latin phrase that means "[a]mong or between themselves". The phrase is "used to to distinguish rights or duties between two or more parties from their rights or duties to others." For example, "The constitutional documents of a company constitute a contract between the company and its shareholders, and between the shareholders inter se." In Australian constitutional law, it refers to matters concerning a dispute between the Commonwealth and one or more of the states concerning the extents of their respective powers.
Usage examples of "inter se".
Nam pulsis Romanis quid aliud quam bella omnium inter se gentium exsistent?
Nec pudor aut pietas continuit quominus impii spoliata Dei templa, occupatas arces, opes publicas, regiones urbis, atque honores magistratuum inter se divisos.
Calabriam adeunt, eamque inter se divisam reperientes funditus depopulati sunt, (or depopularunt,) ita ut deserta sit velut in diluvio.
We only give proper names to the individuals of a species when they differ inter se in practically important respects.