L

LAB:
a system for describing, measuring, and controlling color, using hue, luminance, and brightness established by the International Committee on Illumination (CIE).
LAN:
Local Area Network. High-speed transmissions over twisted pair, coax, or fiber optic cables that connect terminals, personal computers, mainframe computers, and peripherals together at distances of about 1 mile or less.
label paper:
most label paper is coated on one side. Used for labels of various types.
lacquer:
a solution in an organic solvent of a natural or synthetic resin. Used for coating paper to make it less pervious to grease and water, and to provide heat sealing properties, gloss, and aesthetic effects.
laid finish:
finish on bond or text paper on which grids of parallel lines simulate the surface of handmade paper. Laid lines are close together and run against the grain; chain lines are farther apart and run with the grain.
laminated:
paper that is developed by fusing one or more layers of paper together to the desired thickness and quality.
landscape:
artist style in which width is greater than height. (Portrait is opposite.)
lap register:
register where ink colors overlap slightly, as compared to butt register.
laser:
the acronym for light amplification by stimulated emission of radiation. A laser is an intense light beam. For printing, it is capable of transmitting images from digital data.
laser bond:
bond paper made especially smooth and dry to run well through laser printers.
laser-imprintable ink:
ink that will not fade or blister as the paper on which it is printed is used in a laser printer.
latex:
a water dispersion of high polymers form sources related to natural or synthetic rubber. Used in paper manufacturing for such purposes as a coating, adhesive and barrier.
latex adhesives:
requires two layers of latex adhesive, one on the extended flap and the other on the body. When the flap is folded over, the adhesives stick together.
latex seal envelope:
Any envelope with self-sealing adhesive. Requires no moisture.
layout:
the designated position of an envelope in outline on a specific sheet of paper to show image location.
lay edge:
the edge of a sheet of paper feeding into a press.
layout sheet:
form with guidelines to assist designers.
lay flat bind:
method of perfect binding that allows a publication to lie fully open. (Also referred to as  lay flat perfect binding.)
leading:
also known as lead.extra space added between lines of type to space out text and provide visual separation of the lines. Measured in points or fractions . Named after the strips of lead which used to be inserted between lines of metal type. Modern practical usage has blurred the difference between leading and line spacing.
leaf:
one sheet of paper in a publication. Each side of a leaf is one page.
ledger paper:
a strong paper, usually for accounting and records. It is similar to bond paper in its erasure and pen writing characteristics.
legend:
directions about a specific matter (illustrations) and how to use. In regard to maps and tables, an explanation of signs (symbols) used.
letter fold:
two folds creating three panels that allow a sheet of letterhead to fit a business envelope. Also called barrel fold and wrap around fold.
letter paper:
in North America, 8 1/2′ x 11′ sheets. In Europe, A4 sheets.
letterpress printing:
also known as relief typographic printing, letterpress printing employs the use of type or designs cast or engraved in relief (raised) on a variety of surfaces which can include metal, rubber, and wood. In letterpress printing the ink is applied to the raised printing surface. Non-printing areas or spaces are recessed.
letterset:
a printing process combining offset printing with a letterpress relief printing plate.
letterspacing:
the addition of space between the letters of words to increase the line-length to a required width or to improve the appearance of a line.
library picture:
a picture taken from an existing library and not specially commissioned.
ligature:
letters which are joined together as a single unit of type such as oe and fi. Ligatures have long been supported on the Macintosh platform but is not fully supported on the Windows platform.
lightface:
type having finer strokes than the medium typeface. Not used as frequently as medium.
lightweight paper:
book paper with basis weight less than 40# (60 gsm).
lignin:
substance in trees that holds cellulose fibers together. Free sheet has most lignin removed; groundwood paper contains lignin.
line art:
artwork that, unlike a continuous-tone image, has no gradations of tone and, therefore, does not require screening for reproduction in print.
line copy:
any high-contrast image, including type, as compared to continuous-tone copy. Also called line art and line work.
line gauge:
a metal rule used by printers. Divided into Picas it is 72 picas long (11.952in)
line negative:
negative made from line copy.
line screen:
the resolution of a halftone, expressed in lines per inch.
line shot:
a negative image, photographed from mechanical art, that is used for stripping or scanning.
line spacing:
the measurement between lines of type as measured from baseline to baseline. Measured in points or fractions therof. Twelve point type set on 12 pt. line spacing is said to be set solid. Modern practical usage has blurred the difference between leading and line spacing.
linen:
cuttings and threads of linen cloth used in the paper industry for the manufacture of high quality rag content paper.
linen finish:
embossed paper or boards that have a surface resembling linen cloth.
linen tester:
a magnifying glass designed for checking the dot image of a halftone
lithography:
process of printing using a flat-surfaced plate, the image on which is transferred to a blanket then to paper.
live stamp gum adhesives:
there is no top flap gum directly under the position where the postal stamp is placed to avoid blocking
live area:
area on a mechanical within which images will print. Also called safe area.
logo (Logotype):
a┬ácompany or corporate (design) that denotes a unique entity. A possible combination of letters and art work to create a “sole” entity symbol of that specific unit.
long grain:
paper made with the machine direction in the longest sheet dimension.
loose leaf binding:
method allowing insertion and removal of pages in a publication (e.g., trim-4-drill-3).
loose proof:
proof of a halftone or color separation that is not assembled with other elements from a page, as compared to composite proof. Also called first proof, random proof, scatter proof and show-color proof.
loupe:
lens built into a small stand. Used to inspect copy, film, proofs, plates and printing. Also called glass and linen tester.
low key photo:
photo whose most important details appear in the shadows.
lower case:
the small letters in a font of type.
lo-res:
short for low resolution. Low quality reproduction because of a small number of dots or lines per inch.
look up table:
a set of values in tabular form for input or output relationships. Such tables are most often associated with color calibration issues and determining how a color system translates from one color space to another.
LPI:
lines per inch. Measure of resolution for halftones.
luminance:
one of the components of an HSL (hue, saturation, luminance) RGB (red, green, blue) image on a video monitor. It is the highest of the RGB values plus the lowest of the RGB values, dived by two.