Lexis
Most of the vocabulary of modern Bulgarian consists of derivations of some 2,000 words inherited from proto-Slavic through the mediation of Old and Middle Bulgarian. Thus, the native lexical terms in Bulgarian account for 70% to 75% of the lexicon.
The remaining 25% to 30% are loanwords from a number of languages, as well as derivations of such words. The languages which have contributed most to Bulgarian are Russian, Turkish and French. Also Latin and Greek are the source of many words, used mostly in international terminology. Many of the numerous loanwords from Turkish (and, via Turkish, from Arabic and Persian) which were adopted into Bulgarian during the long period of Ottoman rule, have been replaced with native terms. In addition, both specialized (usually coming from the field of science) and commonplace English words (notably abstract, commodity/service-related or technical terms) have also penetrated Bulgarian since the second half of the 20th century, especially since 1989. A noteworthy portion of this English-derived terminology has attained some unique features in the process of its introduction to native speakers and this has resulted in peculiar derivations that slightly set the newly formed loanwords apart from the original words (mainly in pronunciation), although many loanwords are completely identical to the source words. A growing number of international neologisms are also being widely adopted.
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