Introduction chapter. I. Fundamentals of english lexicography

2.3 Specialized (Restricted) Dictionary

Specialized, or restricted, dictionary covers only a certain specific part of the language vocabulary. It deals with:

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  the definite sphere of human activity in which they are used, e.g. in various branches of knowledge, art and trade,
  
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  the type of the units themselves, e.g. phraseological dictionaries,
  
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  the relationships existing between them, e.g. dictionary of antonyms, synonyms, collocations, word frequency, slang, neologisms, etc.
  

Therefore, the main feature of this type of a dictionary is that it registers and explains terms from some definite and restricted field of knowledge of a branch of some science.
The development of a specialized dictionary is closely connected to the development of the spheres of human activity which required special terms for special notions or items and the range of usage of a specialized dictionary is also restricted by a number of people working in these spheres of science, knowledge or art.
In fact, the number of specialized dictionaries is large, and it is increasing each year, therefore we can consider only some subtypes which are relevant for the sphere of linguistics and lexicology.
Pronouncing Dictionary
Pronouncing dictionary is a kind of a dictionary that is in a little need as almost in all cases the pronunciation of words can be inferred from its spelling given in any other dictionary.
Its special feature is that compiling such a dictionary, a lexicographer must make several fundamental decisions about the way pronunciation is to be represented in it. In particular, he must decide what type or types of pronunciation are to be shown; what range of variants is to be included; and what notation system is to be used. Although these questions are not wholly independent of one another, it will be convenient to discuss them in that order.
Pronouncing dictionary is probably the only one type of a dictionary which do not have any exact information based on which it can be compiled.