noun, Arthurian Romance.
a vacant seat at the Round Table that could be filled only by the predestined finder of the Holy Grail and was fatal to pretenders.
(in Arthurian legend) the seat at the Round Table that could be filled only by the knight destined to find the Holy Grail and that was fatal to anyone else
1. a combining form meaning “iron,” used in the formation of compound words: siderolite. 1. a combining form meaning “star,” “constellation,” used in the formation of compound words: siderostat. combining form 1. indicating iron: siderolite sidero- or sider- pref. Iron: sideropenia.
- Si derived unit
SI derived unit (ěs’ī’) Any of the units of measure derived from combinations of the seven base units and two supplementary units of the International System. See Table at measurement.
noun 1. Also called chalybite. a common mineral, iron carbonate, FeCO 3 , usually occurring in yellowish to deep-brown cleavable masses: a minor ore of iron. 2. a meteorite consisting almost entirely of metallic minerals. noun 1. Also called chalybite. a pale yellow to brownish-black mineral consisting chiefly of iron carbonate in hexagonal crystalline form. […]
noun, Astronomy. 1. year (def 4c). sidereal year noun 1. See year (sense 5)