Apotome

2014, Jacques Sesiano (translator), Liber Mahameleth, Part Two: Translation, Glossary, [12th c, Anonymous (possibly John of Seville), Liber Mahameleth], Springer, page 767, If some number and the root of the root of a number are multiplied by the corresponding apotome, the result will be an apotome.

Yet it is not until Book X that the properties of such a line (with greater length is an apotome and lesser length a first apotome) are explained and not until Book XIII that this type of line is applied, which will be discussed in more detail later.[…]The likewise is true of apotomes (X. 97).

1813, Music, article in John Mason Good, Olinthus Gregory, Newton Bosworth, Pantologia: A New Cyclopaedia, Volume 8: MID—OZO, unnumbered page, This semitone was termed by the Pythagoreans apotome, and the diatonic semitone was termed limma. They contended, that the apotome, or distance from B flat to B natural, was larger than the limma, or distance from A to B flat.

For the ratio of the excess of the apotome, above that which is truly a semitone, and which cannot be obtained in numbers, is thus called. This then is demonstrated. To what has been said however, it must be added, that we have called the ratio of d b a semitone, not that a sesquioctave is divided into two equal ratios; for no superparticular ratio is capable of being so divided; but because the followers of Aristoxenus assume a semitone after two sesquioctaves, the ratio of a semitone is assumed, as we have said, according to their position, in order to discover what the ratio is of the comma and apotome to the ratio of the leimma.

The traditional term, from ancient Greek theory, for the diatonic pythagorean semitone is 'limma'; and for the larger, chromatic semitone, ‘apotome’. The oldest extant fretting formula, that of the ninth-century theorist Al-Kindi for the ud (the Arabic lute), is pythagorean. It calls for five frets, to make the following succession of semitones down from nut: limma, apotome, limma, apotome', limma.

The bands pass inside the margins of the apotome as they approach its constriction and form two pigmented areas broadly based on the frontal sutures and becoming dispersed towards the mid-line.

In generalized Diplura, Archaeognatha and some Thysanura, five parts or apotomes are distinguished, which from the anterior to the posterior part are: the presternum, the basisternum, the furcasternum, the spinasternum and the poststernum.