More on the structure of the InterWATER Thesaurus
Updated - Monday 23 October 2006
Preferred term and type of relationship
The thesaurus is an alphabetical presentation, in which each preferred term (or descriptor) and non-preferred term (or non-descriptor) appear in alphabetical order and full details are given of other preferred terms associated with it.
The preferred term, which is the term selected to represent a given concept, forms the basis element of the thesaurus. The types of relationships are shown between preferred terms, and the symbols used to represent them in the thesaurus, are as follows:
| Type of relationship | Cross-reference | Symbol |
| Preferential | Use / used for | Use / uf |
| Hierarchical | Broader term / narrower term | BT / NT |
| Semantic or associative | Related term | rt |
BT1, BT2, etc. and NT1, NT2, etc. are used to indicate the hierarchical levels of broader and narrower terms, respectively, relating to the descriptor. (See Example - relationships). A scope note to define, explain or limit the meaning of the term to which it is applied may supplement descriptors or non-descriptors.
Word-blocks
Preferred terms or descriptors are arranged in word-blocks showing the full structure for each alphabetical entry or in other words, the network of relationships established between the entry-term descriptor and other descriptors in the thesaurus. The word-block displays the complete hierarchy, up or down to permitted maxima of seven levels. In general, a descriptor occurs in a single hierarchy. (See Example - word blocks)
It should perhaps be emphasized that every broader, narrower or related term in a word-block is a descriptor in its own right. Reference to such descriptors in their own alphabetical position, will reveal such scope notes or related terms as have been considered appropriate.
Pre-coordination has been used when such a combination of words represents a frequently used concept (e.g. WATER SUPPLY), thus helping to prevent false coordination during retrieval. Nevertheless, pre-coordination does present a rigidity of terminology that can inhibit the indexer, and it has therefore been used sparingly.
Internationally accepted rules have governed the form of the terminology used. The natural order of words is used in a descriptor; the use of parentheses for inversion is restricted to non-descriptors, where they serve to group sequentially similar pre-coordinated expressions that may be scattered alphabetically. (See Example - terminology)
The alphabetical sequence of the entry terms is word-by-word rather than letter-by-letter. Following the guidelines cited earlier, the plural form has generally been used in the English version. To avoid problems of ambiguity abbreviations have not been used. Diacritics and accents (marks to indicate special phonetic values) have been omitted.
