What is a thesaurus

Q. What is a thesaurus

A. A thesaurus is useful for many things. It is a book of synonyms and antonyms, a dictionary of alternative expressions and a treasury of linguistic equivalents. In short, a useful means of discovering alternative ways of saying exactly the same thing.

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Q. When was the first

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Q. How does Roget's thesaurus work

A. He chose to group his words not alphabetically, but in sequences of closely related ideas. Thus, if an individual was unable to find a suitable synonym in one of the listed categories, he would be able to find it nearby. So, 'rear' is near 'buttocks' and 'poop' and 'back', for example. A more conventional index is published at the back of the book.

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Q. Anything else

A. A thesaurus is also a classified list of terms, particularly keywords, in any one particular field. Thesauri of this kind are designed largely for indexing and searching within a specific subject area. Three types of information will be given in these:

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Preferred Terms: the thesaurus has to indicate which terms indexers and searchers are allowed to use. These terms are called preferred terms. This is a major part of vocabulary control - restricting the vocabulary so that it is easier to predict what words might have been used to index a concept.

Non-preferred Terms: In addition to preferred terms, a thesaurus also needs to indicate some terms that indexers and searchers are not to use. These terms are called non-preferred terms.

Semantic Relations: As well as linking preferred terms with non-preferred terms, a thesaurus also shows links between different preferred terms.

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Q. And when these techniques are applied to database technology

A. A thesaurus is a tool for vocabulary control. By guiding indexers and searchers about which terms to use, it can help to improve the quality of retrieval when setting up links and keywords.

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Q. Why does the name sound like a kind of dinosaur

A. Purely a coincidence. The name comes from the Greek word for a treasury or store-house, thesauros.

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For more on Phrases & Sayings click here

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By Simon Smith