Skip Navigation Bar
NLM logo

A   -   B   -   C   -   D   -   E   -   F   -   G   -   H   -   I   -   L   -   M   -   O   -   P   -   R   -   S   -   T   -   V   -   W

Glossary Credits


-Absorbent floor matting:

Highly absorbent, porous material available in sheets or rolls, often used to wick up small water spills. Some types of synthetic felts can be used to blot liquid from materials or as a drying support or blotter.


Process of drying books or other collection materials through contact with air. See also: Freeze Drying.


Bound materials that include memorabilia such as photographs, newspaper clippings, or scrapbook items.

-Animal/Plant materials:

Objects containing organic materials. Some objects may consist of multiple types of materials.

-Archeological ceramics:

An artifact made of a hard, brittle material produced from nonmetallic minerals by firing at high temperatures.

-Archeological metals:

Historical objects made partly or entirely of metal and metal alloys that may contain unique information about the occupants of a historical site.

-Art on paper:

An aesthetic item or artistic creation on a range of paper-based substrates. Many different types of media can be used, for example, pastels, charcoal, graphite, pen and Ink, acrylic paint, oil paint, gouache, or watercolor, to name a few.

-Audio/Visual recordings (A/V Recordings):

A storage format for sound and moving pictures which include any motion picture film, audio or video tape recordings, and compact discs.

Back to top Arrow point to the top of the page



The outer part of a book which fastens the text block to the boards. Many different types of bindings are possible.

-Bleeding, migration, transfer:

The spreading of soluble media beyond its original location into the surrounding substrate due to contact with liquid; discoloration of the surface of paper due to the movement of residual oils from bindings or printing inks; spreading or transfer of ink or colorant into an adjacent sheet due to contact with liquid.


Wedges, slabs, or cubes made from inert materials (ex: foam) used to support books in a partially open position.


Absorbent material used to soak up water and other liquids, often made from high grade rag or cotton fibers. It is porous with little strength.


Wood, laminated paper sheets, or other base stock used when constructing the covers of a book often covered with another material such as paper, cloth, leather, or vellum.

-Books and bound materials:

A collection of written, printed, illustrated, or blank leaves of paper, parchment , papyrus, or other flexible or semi-flexible material that have been folded, sewn, or attached by adhesive to each other along the binding edge or spine, and usually secured between boards and covered in cloth, paper, or leather.


In cultural heritage collections, bones are human or animal remains from the past.

Back to top Arrow point to the top of the page



Cloth on which artwork is painted usually attached to a stretcher. See also: Stretcher, Framed Artwork, and Painting.


Container, made from plastic or cardboard, used for packing and moving wet collections. Examples include milk crates, and cardboard boxes.

-Case (exhibit):

Enclosure where exhibit items are kept while on display, usually covered and locked.


Materials made out of inorganic, non-metallic solids prepared by the action of heat and subsequent cooling. Examples include pottery, china, and figurines.

-Circular fan:

Device used to provide additional air circulation to collections in humid environments.

-Cloth bound:

A type of binding style in which the boards are covered in cloth. Many different types of cloth may be used, for example: cotton, linen, buckram, silk, or velvet. See also: books and bound materials.

-Coated paper:

glossy/chalky paper: Paper which has had its surface modified by the application of additional materials, such as a mixture of clay and adhesive, with the intent of improving its finish in terms of printability, color, smoothness, opacity, etc. It often appears to have a silky or shiny surface and can be used in the production of posters, magazines, and many modern printed books.

-Composite objects:

Objects made of two or more materials that will react with the environment differently. Reactions that oppose each other in the same painting can cause physical stress and potentially damaging chemical interactions.

-Core (film, microfilm):

Cylinder around which motion picture and microfilm is wound usually made of plastic.


To slowly destroy or damage by eating away, usually by chemical action.

-Corrugated board:

Rigid, paper-based material which consists of a fluted sheet of material sandwiched between two flat sheets, often referred to as cardboard.


The outside part of a bound item, usually consisting of boards with leather, cloth, vellum, or paper attached to them.

Back to top Arrow point to the top of the page



Machine used to remove moisture from the air. Strength and capacity of the machine should be suitable for the dimensions of the space to be dehumidified.


Separation of layers of different materials, having dissimilar rates of expansion and contraction, into individual constituent layers.

-Desiccant Drying:

Moisture is removed from collection items using hydroscopic materials such as silica gel or molecular sieves.


Large canopy or tarp hung from ceiling (from its four corners) underneath water leak. A hose is attached to the center of the diverter leading the water away from the leak and into a drum or large trash can.


A natural or synthetic substance used to add color or change the color of a material.

Back to top Arrow point to the top of the page


-Edge wet:

Refers to a bound item that is only wet or damp around the perimeter. The gutter and center of the text block is not wet.


The process of enclosing sheets of paper (collection items) in inert plastic material which can be sealed on one, two, three, or all four sides. See also: Plastic Enclosure.

-Exhibit items:

Objects on display which may or may not belong to the institution.

Back to top Arrow point to the top of the page


-Fanned Open:

A method of standing a book on its short edge and spreading, or ‘fanning,’ the pages out between the boards to allow air to penetrate into the interior of the book. This assists with air drying bound volumes.

-Fish Glue:

A strong adhesive obtained by heating water that contains the skins, fins, and bones of fish.

-Flaking Media:

Damage caused because of poor adhesion between an object’s support and surface media, or between different paint layers of media.

-Fluid Collections:

Preserved natural science specimens stored in glass jars and kept in specialized storage conditions.


A colorless pungent gas in solution, made by oxidizing methanol.


Evidence of the preserved remains of a once-living organic organism found in rock or soil.

-Framed Artwork:

Paintings, Art on Paper, or other art objects that have been placed in a frame. These may or may not have glazing. See also: glazing.


The process of removing liquid from books or other collection materials through dehydration. Often, the freeze drying process is contracted with a commercial vendor. Three methods are currently available:

1-Sublimation freeze-drying: Method in which frozen water is removed through sublimation; that is, by converting ice directly into water vapor, skipping the liquid phase.

2-Vacuum freeze-drying: Method in which water is removed by placing the item in a partial vacuum. Air pressure is lowered around the item to gently speed drying.

3-Thermal vacuum freeze-drying: Method in which ice is removed by placing the collection item in a partial vacuum while also applying heat. Air pressure is lowered around the item and the remaining air is heated. CAUTION: This method of freeze-drying may be damaging to materials.


The process of stabilizing materials by storing them in a cold environment (below 0° C or 32° F) prior to drying. Freezing helps prevent mold growth (possible if wet/damp collection items remain wet at room temperature), helps keep adjacent wet materials from adhering to one another, and minimizes bleeding and loss of water soluble media in wet collections.

-Freezer paper:

Type of paper used to wrap collections during freezing. It has a plastic or waxy coating that act as a barrier to air and moisture and prevents adhesion of adjacent materials. It is usually available in rolls.


The result of leaving coated paper, photographs, or some other items in contact with each while drying. Fused collection items are difficult to separate without causing some damage.

Back to top Arrow point to the top of the page


-Gelatin images:

Photographs made with a gelatin image layer such as black-and-white or color film and print photographs. The image consists of microscopic silver or color dyes suspended in gelatin layer coated onto paper or film.


The process of converting into a gelatinous form or jelly.

-General collection:

Contemporary collection items not considered rare and hold minimal historical value. Usually, these materials may be “checked out” or removed from the library for patron use.

-Glazed Artwork:

Artwork that is framed using glass, or glazing, covering its surface. See also: Framed artwork.


A substance, made of about 75% silica, that tends to be a transparent solid. It is often fragile and breakable and can be slippery, especially when wet, and sharp around the edges. Glass should be handled carefully.


A thin semitransparent interleaving paper that is somewhat air and water resistant.


Disposable coverings (considered personal protective equipment or PPE) worn to protect hands during the collection recovery process. Two common types of disposable gloves are latex and nitrile. Nitrile gloves are a good alternative for individuals with latex allergies.


The v-shaped interior part of a text block where the pages are joined together. The gutter will be in the center of a bound item when it is open.

Back to top Arrow point to the top of the page


-Hand-colored illustration:

Images painted via a manual application process after printing. The inks and colorants used are often water soluble and therefore prone to bleeding and migration in contact with water or some other liquids.


A collection of dried plant specimens mounted on sheets of paper.

-Hide Glue:

A protein colloid gelatin-like adhesive made from animal connective tissue, formed by boiling down the collagen from skins, bones, tendons and other tissues.

Back to top Arrow point to the top of the page


-Illuminated manuscript:

A bound or flat document with painted pictures, ornamented letters, designs, or a combination thereof, done with pigments, dyes, and often burnished gold or silver.


Books printed with movable metal type which date from c. 1450 - 1501.


Is a design or pattern set or inserted into a surface which is seen in sculpture and the decorative arts.


Material used to separate the pages of books while air drying. This material is absorbent (e.g. plain paper towels with no colorants) or non-absorbent (e.g. freezer paper, spun polyester webbing). It is used while air drying items with gelatin photographs, coated papers or soluble inks and colorants.

-Insoluble salt deposits:

Are sodium-based elements that can take days or weeks to dissolve, causing further damage to object surfaces.

Back to top Arrow point to the top of the page


-Japanese tissue:

A thin, strong handmade paper made from vegetable fibers, frequently used to repair tears in book pages and other paper artifacts.

Back to top Arrow point to the top of the page



A covering material made from an animal skin that has undergone a tanning and dyeing process. Many types of skin are used but the most common tends to be calf, goat, sheep, pig, and deer. See also: Vellum, Parchment.

-Leather bound:

A binding style where the boards are covered either fully or partially in leather.

-full leather: a book bound entirely in leather, whether one piece or several pieces.

-quarter leather: a binding having the spine covered with leather, with the rest of the boards covered with another type of material - usually cloth or paper.

-half leather: a book having a leather spine, extending over approximately one fourth the width of the sides and leather corners, while the remainder of the sides are covered in cloth or paper.

-three-quarter leather: a term applied specifically to a book having leather on the spine and a larger part of the sides, and with enlarged leather corners, while the remainder of the sides are covered with cloth or paper.

-Lending Institution:

The library, museum, or other institution that owns an object and allows another institution to exhibit it. Lenders may also be private collectors. See also: Registrar, Exhibit.

Back to top Arrow point to the top of the page



A manually created as opposed to printed document. See Also: Illuminated manuscript.


Is the art of creating designs using the grain and colors of thin veneers and sometimes other materials. Recesses are carved out and fill in using an adhesive.

-Mat, Artwork:

The paperboard substance surrounding framed artwork. It may or may not be physically attached to the artwork. Care should be taken when removing a mat.


The material (e.g. paint, ink) applied to the substrate (e.g. paper) of a collection item.


Inorganic substances usually having a shiny surface which tend to be good conductors of heat. Entire objects may be made of metal (i.e. coins) or metal may be a component of mixed media (i.e. belts with buckles).


Photographic reproductions of documents at a greatly reduced size, available in several formats:

-Microfilm: microform in rolls, wrapped around a core.

-Microfiche: microform in sheets.


A naturally occurring, homogeneous inorganic solid substance having a definite chemical composition with characteristic crystalline structure, color, and hardness.

-Mineral salts:

Inorganic salts, including, among others, sodium, potassium, calcium, chloride, phosphate, and sulfate. Minerals salts may appear on some items as small, generally white, dots.


Term used to describe a furry biological growth on a surface especially in damp wet environments. Mold can be a health risk and precautions should be taken during mold abatement.

-Active mold: Active mold will smear on a surface and can have a musty smell.

-Inactive mold: This mold is dormant and will look dry and powdery but can become active again in a humid environment.

Back to top Arrow point to the top of the page


-Oil painting:

Artwork created with oil-based paints often with a textured surface that is prone to tackiness when wet. Many oil paintings are done on canvas and framed without glazing. See also: Canvas, Framed Artwork.


An item which is too large to be shelved in normal sequence in the collection area. Often oversized items are shelved flat (horizontally) on the shelf.

Back to top Arrow point to the top of the page



A style of artwork in which liquid media is applied to a substrate with a brush or similar object using either oil or water based media. Many paintings are done on canvas or paper, but other substrates may be used. See also: Oil Painting, Framed Artwork, Art on Paper.

-Paint layer:

A layer of oil paint applied to a support or canvas.


Publications consisting of a few leaves of printed matter stitched together, usually with no boards, and generally only paper covers.


A translucent or opaque material made from the skins of sheep, goats, and similar smaller animals. Parchment and vellum are not tanned (like leather) but are stretched, dried, scraped, and polished for use. See also: Leather, Vellum.

-Partial opening:

Opening a book at an angle of less than 180° that ensures the spine is not stressed. This is accomplished through the placement of support blocks or wedges underneath the covers.

-Partially dry/damp:

A stage during where collection materials can no longer be considered dripping wet, but are not yet dry. Damp materials are still at risk for damage. See also: Edge-wet.

-Photographic materials:

Black and white or colored prints, negatives, slides, glass plates, and transparencies. To reduce damage to these materials, avoid exposing them to light for prolonged periods.

-Plastic enclosures:

Inert polyester housing used to store flat collection items which can be sealed on one, two, three, or four sides. Inert enclosures can also be made from polyethylene or polypropylene.

-Plastic sheeting:

Transparent thick polyethylene sheeting (usually 6 mils thick, available in rolls) is used to cover storage shelving and cabinets during an emergency. The width of the roll should be suitable dimensions for storage shelving.

-Polyester webbing:

A non-absorbent material, purchased in pads or rolls, which can be used as interleaving to prevent adjacent materials from sticking to each other. A special type of felted or thick polyester webbing is used as absorbent floor mats. See also: Interleaving, Spun-polyester webbing, Absorbent Floor Matting.

-Polyethylene sheeting:

Is a chemically inert material that is highly flexible and made into thin sheets or bags. It is used to keep objects from drying out too quickly.

-Pressing board:

A flat plywood or Plexiglas sheet, sometimes used with additional weights (bricks, lead or steel blocks, for example) placed on top of books to dry them. These sheets can also be used to assist in flattening and drying some single sheet items such as photographic prints, paper-based art (e.g. posters), manuscripts and ephemera (usually sandwiched between blotters and polyester webbing). See also: Weights, Blotter, and Polyester Webbing.

-Priming layers:

The first or preliminary coats of size, colorant, and/or isolating layers applied to seal and protect a support surface.

Back to top Arrow point to the top of the page



A plastic or metal sprocketed wheel with film wrapped around hub. The film may be a motion picture or microfilm.


The person at the institution responsible for all items on exhibit.

-Relative humidity (rH):

The ratio of water vapor in the air to the amount which would be present at the same temperature where the atmosphere is fully saturated. rH is expressed as a percentage and can be measured with a moisture meter.

-Resin-coated paper:

A type of plastic coated paper used as photographic print paper after 1960.

-Rewind station:

Machine used to unwind and rewind photographic film or microfilm.

Back to top Arrow point to the top of the page



Process of securing individual signatures (aka quires, gatherings, or sections) together using a needle and thread to form the text block of a bound item.

-Silica gel:

A highly adsorbent form of silicon dioxide used as a dehumidifying and dehydrating agent.

-Slide mount:

Frame placed around transparencies to allow viewing using a slide projector. Common materials include cardboard and plastic. Some mounts incorporate a sandwich of thin glass outside the transparency.

-Soluble inks and colorants:

Dyes or pigments found in felt tip pens, colored pens, ballpoint pens, and stamp ink, to name a few, that bleed or run in contact with water or in a high humid environment.

-Soluble salts:

Sodium-based trace elements that dissolve in water and in contact with moisture in the air.


A thin, blunt metal tool that may be used to gently separate paper or other items from each other under certain circumstances. Also called a microspatula.


An individual animal, plant, or mineral used as an example of its species or type for scientific study or display.

-Specimen collection:

The process of obtaining tissue or fluids for laboratory analysis or testing.


The part of a book which is visible as it stands closed on the shelf, normally showing the title.

-Spun polyester webbing:

A non-absorbent material, purchased in pads or rolls, which can be used to wrap (or interleave) damp or moist materials to prevent adjacent materials from sticking to each other. A special type of felted thick polyester webbing is used as absorbent floor mats. See also: Polyester Webbing, Absorbent Floor Matting.


The process of shifting the covers and text block of a book into its original shape. Squaring up should be done gently, never with much force as wet covers tear easily.

-Squirrel cage fan:

Type of fan used to move air in a humid environment. Moving air helps prevent mold from developing and can aid in drying affected collection items. This device is sometimes also called a centrifugal fan. These fans release air perpendicular to and at a higher speed than the air taken in.

-Stable inks:

Inks and colorants that are insoluble in water. See also: Soluble Inks and Colorants.


The apparatus around which a canvas is stretched. Usually made of wood. See also: Canvas, Painting.

-Study skin:

A zoological specimen that is an animal or part of an animal preserved for scientific use.


The paper, board, skin, wood or any other material that has media applied to it.


Material that physically holds media and is made from canvas, plywood, compressed wood fiberboards, metal, paper or boards.

Back to top Arrow point to the top of the page



The process of preparing, stuffing, and mounting dead creatures to craft a lifelike appearance.


A separating of the paint or ground layers causing oil paint to lift upwards into peaks which resemble a tent

-Text block:

The printed part of a bound item that is between the boards. In adhesive bindings the leaves are glued together along one long edge. In historical items, it consists of multiple signatures (aka quires or sections), sewn together.


Objects made primarily from fabric, or lined with fabric.

Back to top Arrow point to the top of the page



A layer of resin, oil, or solvent applied as a final coating that serves to protects the surface and affects the final appearance.


A translucent or opaque material produced from calfskin, sheepskin or other small animal used as a covering material for bound items or as a material used for writing, printing, or drawing upon. See also: Parchment, Leather.


A thin sheet or layer of a material of superior value or grain glued to the surface of an inferior material.

-Vessel joins:

Evidence of visible mends in previously repaired three-dimensional objects.

Back to top Arrow point to the top of the page


-Wax paper:

A material with a plastic or wax-based coating acting as a barrier to air and moisture used to wrap or interleave affected collection items and prevent adhesion to adjacent materials. It is usually available in rolls. See also: freezer paper.


A steel or lead block, brick or other heavy object used to increase pressure and aid in holding down a rigid board atop a wet or damp collection item. See also: Pressing Board, Blotter, Polyester Webbing, Spun Polyester Webbing.


Objects made from a hard, fibrous material derived from plants. Examples of wooden objects include tools, carvings, and furniture.

Back to top Arrow point to the top of the page

Glossary Credits

Some glossary terms are found in:

Back to top Arrow point to the top of the page

Last Reviewed: September 6, 2018