n. The mass of mineral matter of which the earth, so far as accessible to observation, is made up; a mass, fragment, or piece of that crust, if too large to be designated as a stone, and if spoken of in a general way without special designation of its nature.n. A stone of any size, even a pebble.n. A mass of stone forming an eminence or a cliff.n. Hence, in Scripture, figuratively, foundation; strength; asylum; means of safety; defense.n. A cause or source of peril or disaster: from the wrecking of vessels on rocks: as, this was the rock on which he split.n. A kind of hard sweetmeat, variously flavored.n. Same as rockfish, 1 .n. The rock-dove, Calumba livia, more fully called blue-rock.n. A kind of soap. See the quotation.n. A piece of money: commonly in the plural: as, a pocketful of rocks.n. A very hard kind of cheese, made from skimmed milk, used in Hampshire, England.n. Synonyms It is an error to use rock for a stone so small that a man can handle it: only a fabulous person or a demi-god can lift a rock.To throw stones at; stone.To move backward and forward, as a body supported below (especially on a single point, a narrow line, or a curved base); cause to sway upon a support: as, to rock a cradle; to rock a chair; sometimes, to cause to reel or totter.To move backward and forward in a cradle, chair, etc.To lull; quiet, as if by rocking in a cradle.In engraving, to abrade the surface of, as a copper or steel plate, preparatory to scraping a mezzotinto. See cradle, n., 4 .To cleanse by rocking or shaking about in sand.To affect by rocking in a manner indicated by a connected word or words: as, to rock one into a headache; the earthquake rocked down the houses.To move backward and forward; be moved backward and forward; reel.n. The act of rocking; specifically, a step in fancy dancing.n. A distaff used in hand-spinning; the staff or frame about which the flax or wool is arranged from which the thread is drawn in spinning.n. A young hedgehog.n. See roc.n. A / B ⟨ 7 / 1 ⟩ 5 / 3, A dominates over B;n. A / B ⟨ 5 / 3 ⟩ 3 / 5, A and B are equal or nearly equal;n. A / B ⟨ 3 / 5 ⟩ 1 / 7, B dominates over A;n. A / B ⟨ 1 / 7, B is extreme. Names or terms applicable to and are formed with the prefix per-; those applicable to and are formed with the prefix do-; terms applied to combine two syllables mnemonic of the two factors compared. All igneous rocks fall into five classes, according to the proportions of the salic and femic groups of standard minerals expressing their chemical composition, that is, according to the proportions of the salic and femic minerals in their norms. These minerals are calculated from a chemical analysis of the rock, which may have been obtained by the usual chemical methods, or by calculation from the mineral composition of the rock determined by optical methods. The five classes are: persalane, extremely salic, including rocks high in quartz, feldspar or feldspathoids, corundum or zircon;n. dosalane, dominantly salic, including rocks in which the minerals just mentioned dominate over the femic minerals;n. salfemane, equally, or nearly equally, salic and femic;n. dofemane, dominantly femic;n. perfemane, extremely femic, including such rocks as peridotites and pyroxenites. Each class is divided into five subclasses on the proportions of two subgroups of the predominant group of standard minerals. For salic minerals the subgroups are: quartz, feldspars, feldspathoids;n. corundum, zircon. For femic minerals the subgroups are: pyroxenes, olivin, akermanite, magnetite, hematite, titanite, ihnenite, perofskite, rutile;n. apatite, fluorite, pyrite, etc. Almost all igneous rocks belong to the first subclass in each class. Few are rich in corundum, or zircon, or apatite. Orders are based on the proportions of mineral subdivisions of the preponderant subgroup making a subclass. Thus of the first subgroup of salic minerals, quartz and feldspars are compared with each other, and feldspars and feldspathoids, yielding nine orders in classes 1, 2, 3, as: perquaricn. doquaric, etc. The orders are further divided into sections by comparing the proportions of normative pyroxene with olivin and akermanite, and the proportions of normative minerals having ferric iron with those containing titanium oxid. Rangs are formed on the character of the chemical basis in the groups of standard minerals forming orders. Thus in the first three classes the five rangs are based on the proportions of K2O + Na2O to CaO in the salic minerals, making: peralkalicn. domalkalicn. alkalicalcicn. docalcicn. percalcic. In the last two classes the rangs are based on the proportions of CaO + MgO + FeO to K2O + Na2O in the femic minerals, giving: permirlicn. domirlicn. alkalimirlicn. domalkalicn. peralkalie. Subrangs are based on the proportions of the chemical components within the dominant group of oxids. Thus when the alkalis are dominant the subrangs are: perpotassic.n. dopotassicn. sodipotassicn. dosodicn. persodic. In rangs in which CaO + MgO + FeO dominate sections of rangs are based on the proportions of MgO + FeO compared with CaO, giving: permiricn. domiricn. calcimiricn. docalcicn. percalcic. Subrangs of these are based on the proportions of MgO and FeO, and are: permagnesicn. domagnesicn. magnesiferrousn. doferrousn. perferrous. Grads, the next taxonomic divisions, are based on the proportions of subdivisions of the subordinate group of standard minerals in a manner analogous to the formation of orders; subgrads are based on the chemical characters of these minerals in a manner similar to that followed in forming rangs. The names of other divisions of the system are constructed from geographical names with suffixes peculiar to the different ranks of the system as follows: -ane, class; -one, subclass; -are, order; -ore, suborder; -ase, rang; -ose, subrang; -ate, grad; -ote, subgrad. The termination for the name of a section of any of these is formed by inserting i before the proper suffix.
