(geodynamics, tectonics) A proposed driving force for plate motion in plate tectonics that occurs at mid-ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges.

(geology) a mid-ocean ridge

(geology, oceanography) any of an interconnected system of broad submarine rises formed by plate tectonics

(embryology) A formation of ectodermal cells that occurs at the distal end of each limb bud and functions as the primary signaling point to secure the proper development of a limb.

plural of apical ectodermal ridge

plural of mid-oceanic ridge

plural of mid-ocean ridge

a mostly underwater mountain range on the ocean floor of the Atlantic Ocean about midway between Afro-Eurasia and the Americas; includes Iceland, the Azores, Ascension, St. Helena, Tristan da Cunha and other islands

present participle of round-ridge

Synonym of Warren hoe