Summary This article analyses, from the glothopolitical approach, a series of four monolingual lexicographic works in Argentina published between 1890 and 1903, which are grouped under the category ‘barbarismos dictionaries’. These are linguistic instruments which are prescriptive in nature, since they include and, by extension, exclude certain uses and certain words, as well as describing, describing and assessing the lexical differences between American (Argentinian) and mainland American use at the peak of the mass migratory movement that entered the country. In broad terms, these language instruments report barbarisms, neologisms and foreigners and criticise their use, taking as a parameter the rule of Spanish in Madrid. Here it is argued that those devices expose systems of dominant values and conceptions about language, which go far beyond what is strictly linguistic.