Washitan.
/ˈwɒʃɪtɔː/ a. [Fort Washita, Oklahoma.] (The rocks of) a subdivision of the Cretaceous in the central-southern U.S.A.
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the world > the earth > structure of the earth > age or period > stratigraphic units > [noun] > secondary or Mesozoic > Cretaceous > specific
gault1575
weald clay1822
Wealden1828
Neocomian1845
Washita1860
Albian1863
Fairlight clays1874
Maastrichtian1931
1860 Trans. Acad. Sci. St. Louis 1 586 Washita limestone.—This important member of our Cretaceous System is made up of a nearly white, yellow, gray and blue limestone.
1963 A. Geikie Text-bk. Geol. (ed. 4) II. vi. iii. 1212 The Texas Lower Cretaceous deposits..have been divided into three formations... The highest formation, termed the Washita, consists of four groups.
b. [Ouachita or Washita Mountains, Arkansas.] A porous variety of novaculite used for sharpening cutting tools.
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1885 Spons' Mechanics' Own Bk. 242 Oilstones.—These are of several kinds, the best known being the Charnley Forest, Turkey, Arkansas, and Washita brands.
1938 A. Durst Wood Carving 18 The largest stone shown is the Washita oilstone; the others are various slips for the smaller tools.
1958 J. R. Biggs Woodcuts 32 The knife should be kept sharp on the India or Washita stone.
1974 Encycl. Brit. Micropædia X. 562/2 The Washita Group is the uppermost member of the Comanche Series.
This entry has not yet been fully updated (first published 1986; most recently modified version published online March 2018).
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n.1860