diarch, a. Bot.
(ˈdaɪɑːk)
[f. Gr. δι- twice + ἀρχή beginning, origin.]
Proceeding from two distinct points of origin: said of the primary xylem (or wood) of the root.
| 1884 Bower & Scott De Bary's Phaner. 362 Its xylem is in the great majority of cases..diametrally diarch. Ibid. 363 Triarch and tetrarch bundles sometimes occur in thick roots of species, which are usually diarch. 1887 Hillhouse Strasburger's Pract. Bot. 188 The roots of..ferns are generally diarch. |