Since the beginning of the conquest of the American continent the confrontation of indigenous and European cultures has been observed. Languages, as a part of any culture, an indispensable element of any society respond to the changes in social, political and economic life, respond to the revision of moral and religious values and concepts. This response is revealed in the changes of the structure of the language in general and in the changes of each component of the above-mentioned structure in particular, and it refers to different levels of the language: phonetics, grammar, syntax, vocabulary. Bartomeu Meliá, by analogy with biology, calls the relations between Сastellano (Castilian Spanish) and Guarani a “linguistic ecology”, because language interaction can cause either their flourishing or such changes that can lead to the contamination of the semantics of the words. Semantic transformations have a piecemeal character determined not only by temporal factors, but also by other circumstances among which, along with the geographical aspect, cultural aspect has essential value. The meaning of the words depends on the emotions of the speaker; “substitution of the words and creation of neologisms form speech”. This is in its turn an area of a particular incidence where in one way or another the process of loss of identity has been taking place, whether it is indigenous or Paraguayan language, but we can point it out according to certain features. Language interaction brings enormous potential capacity of future development and enrichment. Thus, for example, the Spanish language in due time was enriched with the Arabic language and later with Anglicisms (Americanisms), etc. We talk here about the borrowings that the recipient language adopts because of its relevant needs. For example, the conquerors brought to America the animals that the native people did not know. These animals were very useful for their everyday life activities. As the Guarani did not have lexical units in their language to name them, they adapted the notions of the Spanish language with certain phonological changes: vaka ‘vaca’(‘cow’), kabayú ‘caballo’ (‘horse’), kabara ‘cabra’ (‘goat’), ovechá ‘obeja’ (‘goat’), etc. In addition to new technologies in all spheres of economic and socio-political life, Europeans reversed the perception of cultural, moral and religious life. They introduced to the daily life the names of the numerals, the months of the year, the days of the week, etc., which the Guarani-speakers accepted as their own. They made them a part of the new system with which the Guarani world had come into contact. For example, to name the days of the week the Guarani have their own notions. Arakõi ‘lunes’(‘Monday’), araapy ‘martes’(‘Tuesday’), etc. Although in everyday life, together with the Guaraní words, Spanish words are used: Oky va’ekue lunes guive ‘it was raining since Monday’ / Haʼe heʼi: “Asẽvaʼerã lunes pyharevete ha aju jueves pyhare” “I was leaving on Monday morning early and coming back Thursday night,” he says. It is important to bear in mind that in the 20th-21st centuries the Guarani appealed to anglicisms to denote the novelties of the modern world: restaurante, güisqui, radio, celular, etc. At the time of initial contacts, the Indians also contributed their first three words to Сastellano (Castilian Spanish): guaraní, mandioca, avatí or, it is better to say, choclo ‘soft corn’. A notable area of semantic transformations comprises the words denoting relationships in Guarani. Contacts with colonizers caused almost no changes in this sphere. As a result, in their speech today we still hear this lexis almost intact, almost without semantic changes, especially in their religious songs, mystical stories. It is about the languages paĩ, mbyá, aché. The words related to the Guarani worldview, their religion in general are of a particular interest from the point of view of the semantic changes. For example, the word guahu ‘song of the Indians’ lost its ritual sense and acquired the rude meaning ‘howl’ or ‘barking of a dog’. However, in certain cases it continues to maintain its original meaning: aguahu papa ‘to sing a dirge; to cry telling things’. Another kotyhu7 ritual song is not even remembered today. Thus, as the result of the intercommunication of two religious cultures on the one hand we find that the Guaraní religious discourse and the poetics of its songs lost their face because of the colonial religious service proficiency. On the other hand, we observe the emergence of a new language: The Christian Guarani with notable differences in semantics compared to so called “classic” Guaraní. Spanish, as the language of the ruling class, privileged during the time of colonization underwent fewer changes at all levels of the system. In the semantic field, the appearance of new meanings or nuances of the discourse markers is distinguished: that is the class of words (homophones of adverbs, conjunctions, collocations, etc., such as: en fin, bueno, verdad, pues, etc. ‘at last, well, true, then or others’) who lost their original meaning due to the process of its dissolution, the function of which is the exhortation, smoothing, etc., of the speech. Un poco ‘a little’ after its adaptation into Guarani, along with its original equivalent, now also corresponds to the standard peninsular Spanish phrase ‘por favor’ (‘please’). Semantic changes of the languages, as a reflection of the changes in social life, caused the emergence of a unique linguistic continuum that characterizes a new society, not just a biological mixture of nations, but a cultural one that let us distinguish Paraguayans from their relatives living in the Rio de la Plata region, Argentina. As a result of the interaction of the two languages, Spanish and Guarani, today in Paraguay “the third language” Jopará exists and is used at all levels of social life.