Abstract
The main aim of the study is to experimentally identify the cognitive perception characteristics of English synonyms corresponding to basic concepts in Kazakh (big–small, sharp–round, dark–light, heavy–light, fast–slow) and to determine their relationship with phonological and semantic factors. Although issues of sound symbolism and prototypicality have been widely studied in global linguistics, these phenomena have not yet been systematically analyzed in the consciousness of Kazakh-speaking respondents on the basis of English lexis. In this respect, the study addresses a relevant research problem in cognitive linguistics and comparative semantics. The experiment involved 67 Kazakh-speaking participants aged 18 and above. Data were collected via the Google Forms platform using the semantic differential method. For each Kazakh concept, four English synonyms were presented, and their degree of correspondence was evaluated on a 5-point Likert scale. The data were processed in the R statistical environment using non-parametric statistical methods (Friedman and Wilcoxon tests with Bonferroni correction). The results revealed the presence of a clear prototypical center for many concepts. In particular, the words big, small, dark, easy, heavy, fast, and slow were perceived as core prototypes, while other synonyms demonstrated peripheral characteristics. For some concepts, the prototypical structure appeared weak or multicentric. Although the symbolic influence of vowels was partially observed, it was not identified as a decisive factor. The findings demonstrate the complex interaction between sound symbolism and prototype theory and provide a theoretical basis for further research.