The article presents the results of a study that examines the impact of sociocultural environment on the development of verbal skills in Romani children aged 7–11 years, with a particular emphasis on children from socially excluded localities. The results are based on a verbal test derived from the Woodcock-Johnson Cognitive Ability Test (WJ IV COG), which was processed using item analysis according to the Rasch model. The main results are based on analysing the differential function of individual items within the verbal tests within the research group (N = 399) compared to the normative sample of the Czech population (N = 936). A secondary goal is to compare Romani children originating from socially excluded areas (N = 204) with those from non-excluded areas (N = 195). Regarding item comparisons between the majority and sample groups, they reveal significant disparities in 14 items (70%) of the Synonyms subtest and 9 items (45%) of the Antonyms subtest. The results highlight the crucial role of a more limited vocabulary, particularly in formal linguistic expressions by Romani children. The presented words representing differently functioning items can also serve as a basis for linguistic analysis and can be applied in assessing educational needs. When comparing the group of children based on their residence in a socially excluded locality, significant differences in the DIF were identified for one item from the Synonyms subtest and three items from the Antonyms subtest.