On the Institution of Music (De institutione musica)

It is called "uncomposite" original: incompositus; meaning a single, undivided musical leap rather than one made of several smaller steps because it is set down as a whole, and no other interval is joined to it; rather, the whole [tone] is placed in individual intervals. In the Chromatic genus one of the three ancient "genera" or styles of tuning, known for its use of semitones, however, the division is placed in a semitone, a semitone, and an uncomposite trihemitone original: triemitonum; an interval of three semitones, similar to a minor third. Therefore, we call this trihemitone "uncomposite" because it is situated within a single interval. For an interval of three semitones can be named in the Diatonic genus when there is a semitone and a tone, but there it is not "uncomposite," for it is completed by two distinct intervals. The same logic applies in the Enharmonic genus. For it consists of a diesis a very small interval, roughly a quarter-tone, another diesis, and an uncomposite ditone an interval of two full tones, similar to a major third, which we call "uncomposite" for the same reason: because it is situated in a single interval.

What Conjunction (Sinaphe) Is. Chapter 24.

With these tetrachords the basic building blocks of Greek music, consisting of four notes spanning a perfect fourth thus arranged and established, sinaphe Greek for "connection" or "conjunction" is what we can call "conjunction" in Latin. This occurs whenever one note continues and joins the end of two tetrachords, as seen in this group of tetrachords:

Here, therefore, is one tetrachord: the hypate, parhypate, licanos, and hypatemeson; and another: the hypatemeson, parhypatemeson, licanosmeson, and mese. In both tetrachords, the note hypatemeson literally "the lowest of the middle strings" is counted; it is the highest note of the first tetrachord and the lowest note of the second. This conjunction is one and the same string: the hypatemeson.

This string joins two tetrachords, just as it joined the hypaton the "low" group and meson the "middle" group tetrachords in the description above. Therefore, sinaphe (which is also called synemmenon) is said to be the conjunction of two tetrachords by a shared middle note—the highest of the former and the lowest of the latter.

What Disjunction (Diezeuxis) Is. Chapter 25.

Diezeuxis Greek for "separation", however, is the name for what can be called "disjunction," which occurs whenever two tetrachords are separated by the space of a full tone, as in these two tetrachords:

Tulis possibly a name or a reference mark

It evidently appears, therefore, that there are two separate tetrachords, since there are eight distinct strings. Diezeuxis, or disjunction, occurs between the mese the "Middle" note and the paramese the note "Next-to-the-Middle", which differ from each other by a full tone. These will be explained more clearly when a later treatise takes up each one to be explained more studiously. But to one looking more carefully, no more than five tetrachords are found: the hypaton (lowest), meson (middle), synemmenon (conjunct), diezeugmenon (disjunct), and hyperboleon (highest).

In What Ways Albinus Named the Strings. Chapter 26.

Albinus likely Albinus the Platonic philosopher, who wrote on music and geometry in the 2nd century AD, in his Latin speech regarding their names, mentioned them thus: he called the hypatae "principals" (principales); the mesae "middles" (medias); the synemmenas "conjunct" (coniunctas); the diezeugmenas "disjunct" (disiunctas); and the hyperboleas "excellent" or "highest" (excellentes). But to us in a foreign...