Also -tomy. [a. Gr. ἀποτομή a cutting off, f. ἀπο-τέμν-ειν to cut off.]
1. Math. The difference of two quantities, commensurable only in power (i.e., in their squares, cubes, etc.; see Euclid Bk. X); e.g., the difference between √2 and 1, which is the difference between the diagonal and side of a square.
1571. Digges, Geom. Pract., IV. i. T iij b. √180–6 … deducted from 12, leueth this Apotome 18–√180.
1656. Blount, Glossogr., Apotomy.
1673. Wallis, in Rigaud, Corr. Sci. Men, II. 567. Of which binomial and apotome, the cubic roots are to be extracted.
1706. in Phillips.
1796. Hutton, Math. Dict., s.v., The doctrine of apotomes, in lines, as delivered by Euclid in the tenth book.
2. Mus. (See quot.)
1696. in Phillips.
1753. Chambers, Cycl. Supp., Apotome, in music, is the difference of the tone major and Limma, expressed by 2187/2048.
1806. Calcott, Mus. Gram., II. iii. 112. This Semitone was termed by the Pythagoreans Apotome.
