Hundreds of thousands of words belong to special scientific, professional or trade terminological systems and are not used or even understood by people outside the particular speciality. Every field of modern activity has its specialized vocabulary. There is a special medical vocabulary, and similarly special terminologies for psychology, botany, music, linguistics, teaching methods and many others.
Term, as traditionally understood, is a word or a word-group which is specifically employed by a particular branch of science, technology, trade or the arts to convey a concept peculiar to this particular activity.
So, bilingual, interdental, labialization, palatalization, glottal stop, descending scale are terms of theoretical phonetics.
There are several controversial problems in the field of terminology. The first is the puzzling question of whether a term loses its terminological status when it comes into common usage. Today this is a frequent occurrence, as various elements of the media of communication (TV, radio, popular magazines, science fiction, etc.) ply people with scraps of knowledge from different scientific fields, technology and the arts. It is quite natural that under the circumstances numerous terms pass into general usage without losing connection with their specific fields.
There are linguists in whose opinion terms are only those words which have retained their exclusiveness and are not known or recognized outside their specific sphere. From this point of view, words associated with the medical sphere, such as unit ("доза лекарственного препарата"), theatre ("операционная"), contact ("носитель инфекции") are no longer medical terms as they are in more or less common usage. The same is certainly true about names of diseases or medicines, with the exception of some rare or recent ones only known to medical men.
There is yet another point of view, according to which any terminological system is supposed to include all the words and word-groups conveying concept peculiar to a particular branch of knowledge, regardless of their exclusiveness. Modern research of various terminological systems has shown that there is no impenetrable wall between terminology and the general language system. To the contrary, terminologies seem to obey the same rules and laws as other vocabulary strata. Therefore, exchange between terminological westerns and the "common" vocabulary is quite normal, and it would be wrong to regard a term as something "special" and standing apart.
Two other controversial problems deal with polysemy and synonymy.
According to some linguists, an "ideal" term should monosemantic (i. e. it should have only one meaning). Polysemantic terms may lead to misunderstanding, and that is a serious shortcoming in professional communication. This requirement seems quite reasonable, yet facts of the language do not meet it. There life, in actual fact, numerous polysemantic terms. The Haguistic term semantics may mean both the meaning Щ& word and the branch of lexicology studying meanings. In the terminology of painting, the term colour may denote hue ("цвет") and, at the same time, stuff used for colouring ("краска").
The same is true about synonymy in terminological stems. There are scholars who insist that terms should not have synonyms because, consequently, scientists and other specialists would name the same objects and phenomena in their field by different terms and would not be able to come to any agreement. This may be true. But, in fact, terms do possess synonyms. ей painting, the same term colour has several synonyms in both its meanings: hue, shade, tint, tinge in the first meaning ("цвет") and paint, tint, dye in the second ("краска").