The concepts studied based on probability from an early age are central to children’s education since, nowadays, we are exposed to a significant volume of data daily, even demanding an understanding of the results of uncertain events. According to the National Common Curricular Base from Brazil, it is key to encourage understanding concepts related to probability from the first years of elementary school. Therefore, in this research, we present the language development process used to indicate the meaning used by students (ages ten and 11) regarding the term uncertainty. Our findings, derived from multivariate textual analyses, have practical implications for educators, policymakers, and researchers in elementary education and probability. They provide insights into the variety of written expressions, symbols, and representations used in the gradual process of learning and acquiring basic concepts in probability. The results reveal the prevalence of words and verbal expressions from a common language, especially related to the intuitive meaning of probability. It is also observed that, as they progress in solving the proposed activities, students assimilate a less intuitive language, moving towards a formal language crucial for understanding concepts related to probability.