The PRINTING United Alliance Glossary serves as an excellent industry terminology resource. It is the language by which we all communicate. Without it, universal understanding would be impossible.

To keep our constituents well informed about changes to the increasingly complex industry terminology, PRINTING United Alliance has developed this glossary of terms. Definitions are for general reference only. Usage may vary between companies, individuals, or national and country customs. The information presented is as accurate as the authors and editors can ascertain and PRINTING United Alliance assumes no responsibility for the use of information presented herein.
  • Shadow dot
    The smallest dots in a halftone negative, or the coarsest or largest in the positive or print.
  • Shadow point
    The darkest tone printable in an image without being black.
  • Sharp fire
    Combustion with excess air and a short flame.
  • Sharp image
    An image where every detail is accurately defined with respect to the original copy or subject; an image with accurate definition of lines and without distorted or fuzzy edges.
  • Sharpen
    To make or become sharp or sharper.
  • Sharpening
    (1) A picture enhancement that creates more distinct borders, areas, lines, or tones: (2) Scanner option that emphasizes detail by increasing the contrast of the boundaries between light and dark areas of an image.
  • Sharpening filters
    A series of digital processes or algorithms that enhance the sharpness of an image.
  • Sharpness
    The line and halftone resolution of detail in an image.
  • Shear
    (1) An action or stress resulting from applied forces that causes or tend to cause two contiguous parts of a body to slide relative to each other in a direction parallel to their plane of contact; the relative movement of adjacent layers in a liquid or plastic during flow; (2) A cutting machine for trimming plastic, laminate, or printed circuit board.
  • Shear adhesion
    Measure of internal strength of an adhesive; i.e. "cohesive" strength.
  • Shear force
    The internal force acting along a plane between two adjacent parts of a material when two equal forces, parallel to that plane, act on each part in opposite directions.
  • Shear mark
    A scar-like imperfection found on some glassware from the cooling action of the shears in cutting the hot glob of glass from the extruder.
  • Shear modulus
    The ratio of the shear stress and the angular shear distortion.
  • Shear strength
    The shear force required to break a specimen divided by its cross sectional area; the force being applied parallel to the cross section area.
  • Shear stress
    Where normal stress is perpendicular to the designated plane, shear stress is parallel to the plane.
  • Shearing strain
    A measure of angular distortion.
  • Shear-thickening
    A phenomenon observed in dilatant fluids where viscosity increases as shear stress increases.
  • Shed
    The open area between warp and weft threads through which a shuttle is passed during weaving.
  • Sheet
    A single piece of paper or other material that is thicker than 254 micrometers (0.010 inches).
  • Sheet caliper
    The thickness of a substrate.
  • Sheet fed
    To mechanically pick-up and place separate sheets of a substrate into a press at predetermined intervals.
  • Sheet label
    Labels that have been produced in sheet form.
  • Sheet matching
    An accurate line-up from sheet to sheet, both vertically and horizontally, when either printing or posting an outdoor poster.
  • Sheeter
    A device on a printing press or converting machine to convert continuous roll lengths into smaller sheet units.
  • Sheeting
    A device to cut stock from continuous roll to individual sheets.