English-Thai Dictionary
graywacke
N หินทรายช นิดหนึ่ง สีเทา ดำ
Webster's 1828 Dictionary
GRAYWACKE
n.A rock somewhat remarkable in its structure and geological relations; a kind of sandstone, composed of grains or fragments of different minerals, chiefly of quartz, feldspar, siliceous slate and argillite. These fragments are sometimes angular, and sometimes their edges and angles are rounded, thus forming nodules or globular masses. The size is very variable, passing from grains to nodules of a foot in diameter. The several ingredients are united by an indurated argillaceous substance, or the interstices between the larger fragments are filled by the same materials which compose the larger parts of the rock, but in grains so comminuted as to resemble a homogeneous cement. The colors are some shade of gray or brown, as bluish gray, reddish brown. etc.
Webster's 1913 Dictionary
GRAYWACKE
Gray "wacke `, n. Etym: [G. grauwacke; grau gray + wacke wacke. See Gray, and Wacke, and cf. Grauwacke. ] (Geol.)
Defn: A conglomerate or grit rock, consisting of rounded pebbles sand firmly united together.
Note: This term, derved from the grauwacke of German miners, was formerly applied in geology to different grits and slates of the Silurian series; but it is now seldom used.
New American Oxford Dictionary
graywacke
gray wacke |ˈgrāˌwak, -ˌwakə ˈɡreɪˌwækə |(Brit. greywacke ) ▶noun Geology a dark coarse-grained sandstone containing more than 15 percent clay. ORIGIN late 18th cent. (as grauwacke ): from German Grauwacke, from grau ‘gray ’ + wacke. The anglicized form dates from the early 19th cent.
Oxford Dictionary
graywacke
gray |wacke ▶noun US spelling of greywacke.
The Wordsmith Dictionary