单词 Dyas 释义 Dyas Geol.|das|[a. Gr. ά: see dyad. After Trias.]A name for the Permian system.1876Page Adv. Text-bk. Geol. xv. 273 The lower red sandstones and magnesian limestones—the Dyas or double group of German geologists.1887Athenum 29 Jan. 163/2...