• acronymAn abbreviation composed of the first letters of a compound term or phrase; e.g. Automatic Teller Machine = ATM, United Nations = UN.
  • associative relationshipA relationship between or among terms in a controlled vocabulary that leads from one term to other terms that are related to or associated with it; begins with the words SEE ALSO or related term (RT).
  • asymmetricLacking symmetry. In the context of controlled vocabularies, reciprocal relationships are asymmetric when the relationship indicator used between a pair of linked terms is different in one direction than it is in the reverse direction, e.g. BT / NT. See also symmetric and reciprocity.
  • authority fileA set of established headings and the cross-references to be made to and from each heading, often citing the authority for the preferred form or variants. Types of authority files include name authority files and subject authority files.
  • authorizationThe process responsible for selecting terms and establishing relationships for a controlled vocabulary.
  • authorizing bodyOversight group responsible for selecting terms and establishing relationships for a controlled vocabulary.
  • blind reference1. A term in a controlled vocabulary that has not been assigned to any content objects. These may be needed in some instances as place holders in taxonomies and other structured vocabularies. 2. A preferred term used in a SEE or USE reference where the term pointed to does not exist in the ...
  • bound termA term consisting of a compound term or phrase that indicates a single concept. (The phrase was originated by Mortimer Taube in his Studies in Coordinate Indexing, vol. 1, 1953, p. 43.) See also compound term.
  • broader termA term to which another term or multiple terms are subordinate in a hierarchy. In thesauri, the relationship indicator for this type of term is BT.
  • browsingThe process of visually scanning through organized collections of representations of content objects, controlled vocabulary terms, hierarchies, taxonomies, thesauri, etc.
  • candidate termA term under consideration for admission into a controlled vocabulary because of its potential usefulness. Also known as provisional term.
  • categoryA grouping of terms that are semantically or statistically associated, but which do not constitute a strict hierarchy based on genus/species, parent/child, or part/whole relationships. See also tree structure.
  • classification schemeA method of organization according to a set of pre-established principles, usually characterized by a notation system and a hierarchical structure of relationships among the entities.
  • compound termA term consisting of more than one word or a phrase that represents a single concept. Compound terms must be constructed according to the guidelines of this Standard. See also bound term and precoordination.
  • conceptA unit of thought, formed by mentally combining some or all of the characteristics of a concrete or abstract, real or imaginary object. Concepts exist in the mind as abstract entities independent of terms used to express them.
  • concept mapA representation in two dimensions of the conceptual relationships among terms and the concepts they represent.
  • content objectAn entity that contains data/information. A content object can itself be made up of content objects. For example, a journal is a content object made up of individual journal articles, which can each be a content object. The text, figures, and photographs included in a journal article can also be ...
  • controlled vocabularyA list of terms that have been enumerated explicitly. This list is controlled by and is available from a controlled vocabulary registration authority. All terms in a controlled vocabulary must have an unambiguous, non-redundant definition. NOTE: This is a design goal that may not be true in ...
  • cross-reference1. A direction from one term to another. See associative relationship; equivalence relationship; hierarchical relationship.
  • documentAny item, printed or otherwise, that is amenable to cataloging and indexing. The term applies not only to written and printed materials in paper or microform versions (e.g., books, journals, maps, diagrams), but also to non-print media (e.g., machine-readable records, transparencies, audiotapes, ...
  • entry termThe non-preferred term in a cross reference that leads to a term in a controlled vocabulary. Also known as “lead-in term” In thesauri, the relationship indicator for this type of term is U (USE); its reciprocal is UF (USED FOR). See also preferred term.
  • entry vocabularyThe set of non-preferred terms (USE references) that lead to terms in a controlled vocabulary. NOTE: This term is used by some controlled vocabulary designers to represent the preferred as well as the non-preferred terms in a controlled vocabulary.
  • eponymA term incorporating the name of a real or mythical person, generally the discoverer of a phenomenon or inventor of an object, e.g., Herculean labor, Parkinson's disease, pasteurization.
  • equivalence relationshipA relationship between or among terms in a controlled vocabulary that leads to one or more terms that are to be used instead of the term from which the cross-reference is made; begins with the word SEE or USE.
  • facetA grouping of concepts of the same inherent category. Examples of categories that may be used for grouping concepts into facets are: activities, disciplines, people, materials, places, etc.
  • false hitA content object retrieved whose content does not match the intent of the concepts represented by the search terms used. Previously called false drop.
  • filing rulesA set of guidelines that determine how letters and numbers, spaces, and special characters will be treated in assembling an alphabetical or other listing.
  • flat formatAn alphabetical display format of controlled vocabularies in which only one level of broader terms and one level of narrower terms are shown for each term.
  • focusIn a compound term, the noun component that identifies the class of concepts to which the term as a whole refers. Also known as head noun. See also modifier.
  • free textAntonym of controlled vocabulary. Natural language terms appearing in content objects, which can complement controlled vocabulary terms in an information storage and retrieval system. In free text searching, controlled vocabulary terms can also be retrieved. See also keyword.
  • generic posting1. In controlled vocabularies, the treatment of narrower terms as equivalents, e.g., furniture UF beds; UF sofas. See also upposting. 2. In indexing and subject cataloging, the assignment of a broader term instead of a specific term, e.g., furniture to a content object on sofas.
  • generic structureA controlled vocabulary format that indicates all hierarchical levels of terms within an alphabetic display by means of codes, indentation, and/or punctuation marks.
  • glossAn explanation or definition of an obscure or ambiguous word in a text. See also qualifier.
  • graphics displayA method of representing information that uses space and distance in addition to words.
  • headingA preferred name or term. Types of headings include proper name headings (which may be called identifiers), subject headings, and terms. A heading may include a qualifier.
  • hierarchical relationship. A relationship between or among terms in a controlled vocabulary that depicts broader (generic) to narrower (specific) or whole-part relationships; begins with the words broader term (BT), or narrower term (NT).
  • hierarchyBroader (generic) to narrower (specific) or whole-part relationships, which are generally indicated in a controlled vocabulary through codes or indentation. See also broader term; narrower term.
  • history noteA note in a term record in a controlled vocabulary that provides the date of entry of a term as well as the history of modifications to its scope, relationships, etc.
  • homographOne of two or more words that have the same spelling, but different meanings and origins. In controlled vocabularies, homographs are generally distinguished by qualifiers.
  • HTMLA markup language used to describe the layout and presentation of a document on the World Wide Web.
  • hyperlinkA method of using embedded links to connect different parts of a content object to one another.
  • identifier1. A proper name (or its abbreviation or acronym) of an institution, person, place, object, or process, optionally treated as a category of heading distinct from terms. Identifiers may be held in a separate file (compare authority file), and their form may be controlled (e.g., the name of an ...
  • indexing1. A method by which terms or subject headings from a controlled vocabulary are selected by a human or computer to represent the concepts in or attributes of a content object. The terms may or may not occur in the content object. 2. An operation intended to represent the results of the content ...
  • indexing languageA controlled vocabulary or classification system and the rules for its application. An indexing language is used for the representation of concepts dealt with in documents [content objects] and for the retrieval of such documents [content objects] from an information storage and retrieval ...
  • indexing termThe representation of a concept in an indexing language, generally in the form of a noun or noun phrase. Terms, subject headings, and heading-subheading combinations are examples of indexing terms.
  • information storage and retrieval systemA set of operations and the associated equipment, software, and documentation by which content objects are indexed and the data are stored, so that selected content objects can be retrieved in response to requests employing commands that can be handled by the system.
  • initialismA set of initials by which something is known in preference to the full form of its name. Example: IBM, ICBM. See also acronym.
  • interoperabilityThe ability of two or more systems or components to exchange information and use the exchanged information without special effort on the part of either system.
  • keywordA word occurring in the natural language of a document that is considered significant for indexing and retrieval. See also free text.
  • KWIC indexA type of index, arranged alphabetically, in which each significant word in a string of text serves as an access point, by being graphically emphasized and surrounded by the rest of the string. The keyword is generally in a centered column and is followed on the right by the continuation of the ...
  • KWOC indexA type of index, arranged alphabetically, in which each significant word in a string of text serves as an access point, usually positioned in the left-hand column of a page, followed by the complete string. The keyword may therefore not be in the immediate context of the words that surround it.
  • lexemeA fundamental unit of the vocabulary of a language.
  • lexical databaseA database containing terms as well as information about the terms such as part of speech, type of term, etc.
  • lexicographerA person who is knowledgeable about terms, their uses, parts of speech, etc. Lexicographers often construct controlled vocabularies.
  • literary warrantJustification for the representation of a concept in an indexing language or for the selection of a preferred term because of its frequent occurrence in the literature. See also organizational warrant and user warrant.
  • mappingA set of correspondences between categories, schema element names, or controlled terms. Mappings are used for transforming data or queries from one vocabulary for use with another.
  • metasearchingThe simultaneous searching across multiple databases, sources, platforms, and protocols. Also known as broadcast searching, cross-database searching, federated searching, or parallel searching.
  • microcontrolled vocabularyA subset of a controlled vocabulary, covering a limited range of topics within the domain of the controlled vocabulary. A microcontrolled vocabulary may contain highly specialized terms that are not in the broad controlled vocabulary. Such terms should map to the hierarchical structure of the ...
  • modifierIn a compound term, one or more components that serve to narrow the extension of a focus and specify one of its subclasses. Also known as difference.
  • multilevel hierarchyA set of hierarchical relationships among terms that has multiple levels of specificity extending from the most broadly defined terms to the most specific.
  • narrower termA term that is subordinate to another term or to multiple terms in a hierarchy. In thesauri, the relationship indicator for this type of term is NT.
  • natural languageA language used by human beings for verbal communication. Words extracted from natural language texts for indexing purposes without vocabulary control are often called keywords.
  • navigationThe process of moving through a controlled vocabulary or an information space via some pre-established links or relationships. For example, navigation in a controlled vocabulary could mean moving from a broader term to one or more narrower terms using the predefined relationships.
  • near-synonymA term whose meaning is not exactly synonymous with that of another term, yet which may nevertheless be treated as its equivalent in a controlled vocabulary. Example: salinity, saltiness
  • node labelA “dummy” term, often a phrase, that is not assigned to documents when indexing, but which is inserted into the hierarchical section of some controlled vocabularies to indicate the logical basis on which a class has been divided. Node labels may also be used to group categories of related ...
  • non-preferred term
  • OPAC (Online Public Access Catalog)A library or other catalog of content objects that is accessible online. The catalog may or may not be accessible to the public, but it is still called an OPAC.
  • organizational warrantJustification for the representation of a concept in an indexing language or for the selection of a preferred term due to characteristics and context of the organization. See also literary warrant and user warrant.
  • orphan termA term that has no associative or hierarchical relationship to any other term in a controlled vocabulary.
  • orthographyThe art of writing words with the proper letters according to standard usage.
  • PDFA file format developed by Adobe Systems that provides hardwareand software-independent viewing of a formatted document.
  • permuted displayA type of index where individual words of a term are rotated to bring each word of the term into alphabetical order in the term list. See also KWIC and KWOC.
  • pick listA graphical user interface device that allows the user to select from a pre-set list of terms. Typically the list of terms is shown when the user clicks on a down arrow next to the entry box for the term.
  • polyhierarchyA controlled vocabulary structure in which some terms belong to more than one hierarchy. For example, rose might be a narrower term under both flowers and perennials in a horticulture vocabulary.
  • polysemeA word with multiple meanings. In spoken language, polysemes are called homonyms; in written language they are called homographs. Only the latter are relevant to controlled vocabularies designed for textual information.
  • postcoordinationThe combining of terms at the searching stage rather than at the subject heading list construction stage or indexing stage. See also precoordination.
  • postingsThe number of content objects to which a term is assigned.
  • precisionA measure of a search system's ability to retrieve only relevant content objects. Usually expressed as a percentage calculated by dividing the number of retrieved relevant content objects by the total number of content objects retrieved. A high-precision search ensures that, for the most part, ...
  • precoordinationThe formulation of a multiword heading or the linking of a heading and subheadings to create a formally controlled, multi-element expression of a concept or object. Precoordination is often used to ensure logical sorting of related expressions. Examples of precoordinated headings: New England ...
  • preferred termOne of two or more synonyms or lexical variants selected as a term for inclusion in a controlled vocabulary. See also non-preferred term. NOTE: In the previous version of this Standard, a preferred term was known as a descriptor.
  • qualifierA defining term, used in a controlled vocabulary to distinguish homographs. A qualifier is considered part of a term, subject heading, or entry term, but is separated from it by punctuation. The qualifier is generally enclosed in parentheses. Example: Mercury (metal) See also gloss.
  • recallA measure of a search system's ability to retrieve all relevant content objects. Usually expressed as a percentage calculated by dividing the number of retrieved relevant content objects by the number of all relevant content objects in a collection. A high recall search retrieves a comprehensive ...
  • reciprocitySemantic relationships in controlled vocabularies must be reciprocal, that is each relationship from one term to another must also be represented by a reciprocal relationship in the other direction. Reciprocal relationships may be symmetric, e.g. RT / RT, or asymmetric e.g. BT / NT. See also ...
  • relación de equivalencia
  • related termA term that is associatively but not hierarchically linked to another term in a controlled vocabulary. In thesauri, the relationship indicator for this type of term is RT.
  • relationship indicatorA word, phrase, abbreviation, or symbol used in thesauri to identify a semantic relationship between terms. Examples of relationship indicators are UF (USED FOR), and RT (related term).
  • romanizationThe conversion of a non-roman script by means of transcription or transliteration or a combination of the two methods.
  • running headA page heading indicating the first and last entries that appear on that page. The heading changes on each page to reflect the changed content.
  • scope noteA note following a term explaining its coverage, specialized usage, or rules for assigning it.
  • semantic linkingA method of linking terms according to their meaning or meanings.
  • semantic webA representation in two (or possibly three) dimensions of the semantic relationships between and among terms and the concepts they represent.
  • siblingA term that shares the same broader term (one level higher) as other terms.
  • stop listA list of words considered to be of no value for retrieval. It consists primarily of function words “articles, conjunctions, and prepositions” but may also include words that occur very frequently in the literature of a domain.
  • subheadingA term appended to a heading in order to modify or delimit the heading by indicating a particular aspect or relationship pertaining to it. A term with a subheading may be subject to further modification. See also precoordination.
  • subject headingA word or phrase, or any combination of words, phrases, and modifiers used to describe the topic of a content object. Precoordination of terms for multiple and related concepts is a characteristic of subject headings that distinguishes them from controlled vocabulary terms. See also ...
  • subject heading listAn alphabetical list of subject headings with cross-references from non-preferred terms and links to related terms. These lists often include separate sequences of standardized subheadings that may be combined with all or only some subject headings. Rules for applying subheadings usually ...
  • symmetricHaving symmetry. In the context of controlled vocabularies reciprocal relationships are symmetric when the relationship indicator used between a pair of linked terms is the same in one direction as it is in the reverse direction, e.g. RT / RT. See also asymmetric and reciprocity.
  • synonymA word or term having exactly or very nearly the same meaning as another word or term.
  • synonym ringA group of terms that are considered equivalent for the purposes of retrieval.
  • taxonomyA collection of controlled vocabulary terms organized into a hierarchical structure. Each term in a taxonomy is in one or more parent/child (broader/narrower) relationships to other terms in the taxonomy.
  • termOne or more words designating a concept. See also compound term, entry term, and precoordinated term.
  • term recordA collection of information associated with a term in a controlled vocabulary, including the history of the term, its relationships to other terms, and, optionally, authorities for the term.
  • thesaurusA controlled vocabulary arranged in a known order and structured so that the various relationships among terms are displayed clearly and identified by standardized relationship indicators. Relationship indicators should be employed reciprocally. Its purpose is to promote consistency in the ...
  • top termThe broadest term in a controlled vocabulary hierarchy, sometimes indicated by the abbreviation TT.
  • transcriptionThe process of recording the phonological and/or morphological elements of a language in terms of a specific writing system.
  • transliterationThe process of recording the graphic symbols of one writing system in terms of the corresponding graphic symbols of another writing system.
  • tree structureA controlled vocabulary display format in which the complete hierarchy of terms is shown. Each term is assigned a tree number or line number which leads from the alphabetical display to the hierarchical one. The hierarchical display is also known as a systematic display.
  • typographyThe style, arrangement, appearance, or typeface used to represent information.
  • up-postingThe automatic assignment of broader terms in addition to the specific term by which a document is indexed. Also known as autoposting. See also generic posting.
  • user interfaceThe way in which a user interacts with a computer-based system.
  • user warrantJustification for the representation of a concept in an indexing language or for the selection of a preferred term because of frequent requests for information on the concept or free-text searches on the term by users of an information storage and retrieval system. See also literary warrant and ...
  • vocabulary controlThe process of organizing a list of terms (a) to indicate which of two or more synonymous terms is authorized for use; (b) to distinguish between homographs; and (c) to indicate hierarchical and associative relationships among terms in the context of a controlled vocabulary or subject heading ...