Caustic surface

Surface Sur"face`, n. [F. See {Sur-}, and {Face}, and cf. {Superficial}.] 1. The exterior part of anything that has length and breadth; one of the limits that bound a solid, esp. the upper face; superficies; the outside; as, the surface of the earth; the surface of a diamond; the surface of the body. [1913 Webster]

The bright surface of this ethereous mold. --Milton. [1913 Webster]

2. Hence, outward or external appearance. [1913 Webster]

Vain and weak understandings, which penetrate no deeper than the surface. --V. Knox. [1913 Webster]

3. (Geom.) A magnitude that has length and breadth without thickness; superficies; as, a plane surface; a spherical surface. [1913 Webster]

4. (Fort.) That part of the side which is terminated by the flank prolonged, and the angle of the nearest bastion. --Stocqueler. [1913 Webster]

{Caustic surface}, {Heating surface}, etc. See under {Caustic}, {Heating}, etc.

{Surface condensation}, {Surface condenser}. See under {Condensation}, and {Condenser}.

{Surface gauge} (Mach.), an instrument consisting of a standard having a flat base and carrying an adjustable pointer, for gauging the evenness of a surface or its height, or for marking a line parallel with a surface.

{Surface grub} (Zo["o]l.), the larva of the great yellow underwing moth ({Triph[oe]na pronuba}). It is often destructive to the roots of grasses and other plants.

{Surface plate} (Mach.), a plate having an accurately dressed flat surface, used as a standard of flatness by which to test other surfaces.

{Surface printing}, printing from a surface in relief, as from type, in distinction from plate printing, in which the ink is contained in engraved lines. [1913 Webster]