idoneum
Idoneum is a term of Latin origin tied to the adjective idoneus, which means fit, suitable, or proper. In Latin grammar, idoneum represents the neuter singular form of the adjective. As a standalone noun, idoneum is unusual and attested mainly in scholarly or glossarial contexts to signify the idea of suitability or the thing that is fitting for a given purpose. Because it is not a standard lexical item in classical Latin, its appearance is primarily of interest to philologists and students examining medieval or post-classical Latin texts.
Historically, idoneum has been encountered in discussions of value, appropriateness, or suitability within a given framework,
In English, the descendants or equivalents are best represented by idoneous or idoneal, both meaning suitable
Idoneus, idoneous, idoneal, suitability
As with many classical terms, use and meaning can vary by manuscript context. Scholarly glossaries and Latin