decussate

Etymology

Borrowed from Latin decussātus from decussāre (“to divide crosswise, arrange crosswise or mark with a cross”), from decussis (“a 10 asses coin”), from decem (“ten”) + as (“a Roman coin”). Based on the cross marking on the decussis coin.

adj

1. Crossed; intersected; resembling a letter X.
2. (zoology) Having anatomical structures or markings crossing each other, typically in an X shape or at right angles.
3. (botany) Having opposite leaves arranged alternately at right angles.
   Juniperites, ju-ne-per-i′tis, s[ubstantive]. A genus of fossil plants, in which the branches are ranged irregularly; leaves short, obtuse, inserted by a broad base, opposite, decussate, and arranged in four rows. 1849, John Craig, “Juniperites”, in A New Universal Etymological, Technological, and Pronouncing Dictionary of the English Language, Embracing All the Terms Used in Art, Science, and Literature, volumes II (Jac–Zyt), London: Published (for the proprietors,) by Henry George Collins, 22 Paternoster Row, →OCLC, page 15
4. (rhetoric) Consisting of two rising and two falling clauses, placed in alternate opposition to each other.
   a decussated period

verb

1. To form an X or to cross or intersect.
   The two trochlears decussate in the anterior medullary velum. 1949, Herbert Eugene Walter, Leonard Perkins Sayles, Biology of the Vertebrates