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Webster’s Dictionary (1828)

98,828 entries. Headwords are matched first, then definition text.

13 words match “GNEISS”

GNEISS n.
ende sometimes takes the place of the mica, and it is then called hornblendic or syenitic gneiss. Similar varieties of related rocks are also called gneiss.
GNEISSIC a.
Relating to, or resembling, gneiss; consisting of gneiss.
GNEISSOID a.
Resembling gneiss; having some of the characteristics of gneiss; -- applied to rocks of an intermediate character between granite and gneiss, or mica slate and gneiss.
GNEISSOSE a.
Having the structure of gneiss.
ARKOSE n.
A sandstone derived from the disintegration of granite or gneiss, and characterized by feldspar fragments. -- Ar*kos"ic (#), a.
GRADUATE v.
To pass by degrees; to change gradually; to shade off; as, sandstone which graduates into gneiss; carnelian sometimes graduates into quartz.
GRANITE n.
eldspar, and mica, and usually of a whitish, grayish, or flesh-red color. It differs from gneiss in not having the mica in planes, and therefor in being destitute of a schistose structure.
GRANITOID a.
Resembling granite in granular appearance; as, granitoid gneiss; a granitoid pavement.
HYPOGENE a.
Formed or crystallized at depths the earth's surface; -- said of granite, gneiss, and other rocks, whose crystallization is believed of have taken place beneath a great thickness of overlying rocks. Opposed to epigene.
PRIMARY a.
have been first formed, being crystalline and containing no organic remains, as granite, gneiss, etc.; -- called also primitive rocks. The terms Secondary, Tertiary, and Quaternary rocks have also been used in like manner, but of these the last two only are now in use. -- Primary salt (Chem.), a salt derived from a p…
PROTOGINE n.
A kind of granite or gneiss containing a silvery talcose mineral.
SLATY a.
s now believed to be caused by the compression which the strata have undergone. -- Slaty gneiss (Min.), a variety of gneiss in which the scales of mica or crystals of hornblende, which are usually minute, form thin laminæ, rendering the rock easily cleavable.
ZEOLITE n.
in in the cavities of amygdaloid, basalt, and lava, also, less frequently, in granite and gneiss. So called because many of these species intumesce before the blowpipe. Needle zeolite, needlestone; natrolite.