Scale (skāl), n. [AS. scāle; perhaps influenced by the kindred Icel. skāl balance, dish, akin also to D. schaal a scale, bowl, shell, G. schale, OHG. scāla, Dan. skaal drinking cup, bowl, dish, and perh. to E. scale of a fish. Cf. Scale of a fish, Skull the brain case.] 1. The dish of a balance; hence, the balance itself; an instrument or machine for weighing; as, to turn the scale; -- chiefly used in the plural when applied to the whole instrument or apparatus for weighing. Also used figuratively.
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Long time in even scale
The battle hung. Milton.
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The scales are turned; her kindness weighs no more
Now than my vows. Waller.
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2. pl. (Astron.) The sign or constellation Libra.
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Platform scale. See under Platform.
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Scale, n. [Cf. AS. scealu, scalu, a shell, parings; akin to D. schaal, G. schale, OHG. scala, Dan. & Sw. skal a shell, Dan. skiæl a fish scale, Goth. skalja tile, and E. shale, shell, and perhaps also to scale of a balance; but perhaps rather fr. OF. escale, escaile, F. écaille scale of a fish, and écale shell of beans, pease, eggs, nuts, of German origin, and akin to Goth. skalja, G. schale. See Shale.] 1. (Anat.) One of the small, thin, membranous, bony or horny pieces which form the covering of many fishes and reptiles, and some mammals, belonging to the dermal part of the skeleton, or dermoskeleton. See Cycloid, Ctenoid, and Ganoid.
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Fish that, with their fins and shining scales,
Glide under the green wave. Milton.
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2. Hence, any layer or leaf of metal or other material, resembling in size and thinness the scale of a fish; as, a scale of iron, of bone, etc.
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3. (Zoöl.) One of the small scalelike structures covering parts of some invertebrates, as those on the wings of Lepidoptera and on the body of Thysanura; the elytra of certain annelids. See Lepidoptera.
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4. (Zoöl.) A scale insect. (See below.)
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5. (Bot.) A small appendage like a rudimentary leaf, resembling the scales of a fish in form, and often in arrangement; as, the scale of a bud, of a pine cone, and the like. The name is also given to the chaff on the stems of ferns.
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6. The thin metallic side plate of the handle of a pocketknife. See Illust. of Pocketknife.
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7. An incrustation deposit on the inside of a vessel in which water is heated, as a steam boiler.
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8. (Metal.) The thin oxide which forms on the surface of iron forgings. It consists essentially of the magnetic oxide, Fe3O4. Also, a similar coating upon other metals.
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Covering scale (Zoöl.), a hydrophyllium. -- Ganoid scale. (Zoöl.) See under Ganoid. -- Scale armor (Mil.), armor made of small metallic scales overlapping, and fastened upon leather or cloth. -- Scale beetle (Zoöl.), the tiger beetle. -- Scale carp (Zoöl.), a carp having normal scales. -- Scale insect (Zoöl.), any one of numerous species of small hemipterous insects belonging to the family Coccidæ, in which the females, when adult, become more or less scalelike in form. They are found upon the leaves and twigs of various trees and shrubs, and often do great damage to fruit trees. See Orange scale,under Orange. -- Scale moss (Bot.), any leafy-stemmed moss of the order Hepaticæ; -- so called from the small imbricated scalelike leaves of most of the species. See Hepatica, 2, and Jungermannia.
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Scale, v. i. 1. To separate and come off in thin layers or laminæ; as, some sandstone scales by exposure.
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Those that cast their shell are the lobster and crab; the old skins are found, but the old shells never; so it is likely that they scale off. Bacon.
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2. To separate; to scatter. [Scot. & Prov. Eng.]
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Scale, v. t. [Cf. It. scalare, fr. L. scalae, scala. See Scale a ladder.] To climb by a ladder, or as if by a ladder; to ascend by steps or by climbing; to clamber up; as, to scale the wall of a fort.
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Oft have I scaled the craggy oak. Spenser.
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