Abbreviation: Designation formed by omitting words or letters from a longer form and designating the same concept. (ISO 1087-1:2000)
Acronym: Abbreviation made up of the initial letters of the components of the full form of the designation or from syllables of the full form and pronounced syllabically. (ISO 1087-1:2000) NOTE: Acronyms examples: laser, DOS, GATT, UNESCO, UNICEF.
Category: A broad facet, primary division of a special classification system or of a main class of a general one. (ISO 5217)
Classification: Arrangement of symbols indicating concepts into classes and their subdivisions to express generic relations or other types of relations between them. (ISO 5127:2001)
Concept: Unit of knowledge created by a unique combination of characteristics. (ISO 1087-1:2000)
Data: A reinterpretable representation of information in a formalized manner suitable for communication, interpretation, or processing. (ISO/IEC 2382-1:1993)
Designation: Representation of a concept by a sign which denotes it. (ISO 1087-1:2000) NOTE: In terminology work three types of designations are distinguished: symbols, appellations and terms.
Equivalent Term: Term related to another by an equivalence relation. (ISO 5127:2001)
Glossary: Terminological dictionary which contains a list of designations from a subject field, together with equivalents in one or more languages. NOTE: In English common language usage, glossary can refer to a unilingual list of designations and definitions in a particular subject field. (ISO 1087:2000).
Language: System of signs for communication usually consisting of a vocabulary and rules. (ISO 5127:2001)
Ontology: A reference tool containing an explicit formal specification of how to represent the objects, concepts and other entities that are assumed to exist in some area of interest and the relationships that hold among them. NOTE: The subject of ontology is the study of the categories of things that exist or may exist in some domain. The product of such a study, called ontology, is a catalog of the types of things that are assumed to exist in a domain of interest D from the perspective of a person who uses a language L for the purpose of talking about D. The types in the ontology represent the predicates, word senses, or concept and relation types of the language L when used to discuss topics in the domain D. (John Sowa cofounder of VivoMind Intelligence, Inc.)
Preferred Term: 1) Term rated according to the scale of the term acceptability rating as the primary term for a given concept. (ISO 1087-1:2000) 2) Index term of a thesaurus used in preference to an alternative and equivalent entry term to which it is related. (ISO 5127:2001)
Related Term (RT): Index term with a coordinate relation and equal rank to another index term. (ISO 5127:2001) NOTE: A related term is of associated meaning but not synonymous with the other term.
Search and Retrieval: Operations accomplished to obtain information about documents through a retrieval system (ISO5127:2001).
Semantic Web: The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation.
Special Language: Synonym: language for special purposes. Language used in a subject field and characterized by the use of specific linguistic means of expression. NOTE: The specific linguistic means of expression always include subject-specific terminology and phraseology and also may cover stylistic or syntactic features. (ISO 1087-1:2000)
Synonomy: Relation between or among terms in a given language representing the same concept. (ISO 1087-1:2000) EXAMPLE: Category-class; deuterium-heavy hydrogen.
Term: Verbal designation (3.4.1) of a general concept in a specific subject field. (ISO 1087-1:2000) NOTE: A term may contain symbols and can have variants, e.g. different forms of spelling.
Terminology: Set of designations belonging to one special language. (ISO 1087-1:2000)
Terminological Dictionary: Synonym: technical dictionary. Collection of terminological entries presenting information related to concepts or designations from one or more specific subject fields. (ISO 1087-1:2000)
Terminological Entry: Part of a terminological data collection which contains the terminological data related to one concept. (ISO 1087-1:2000)
Terminology Science: Science studying the structure, formation, development, usage and management of terminologies in various subject fields. (ISO 1087-1:2000)
Thesaurus: Controlled vocabulary including equivalent terms interrelations and rules of application. (ISO 5127:2001)
Word: Smallest linguistic unit conveying a specific meaning and capable of existing as a separate unit in a sentence. (ISO 5127:2001)
Please read also the Glossary of Terms used in Terminology prepared by the University of Genève and the University of Manchester Institute of Science and Technology.