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.
6. The thin metallic side plate of the handle of a pocketknife. See
Illust. of Pocketknife.
7. An incrustation deposit on the inside of a vessel in which water is
heated, as a steam boiler.
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.
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.
Scale (?), v. t. 1. To strip or clear of scale or scales; as, to scale
a fish; to scale the inside of a boiler.
2. To take off in thin layers or scales, as tartar from the teeth; to
pare off, as a surface. "If all the mountains were scaled, and the
earth made even." T. Burnet.