The dataset from the small world of words project is a large-scale scientific study constructing a mental lexicon—a dictionary of word meanings and associations—across major world languages. It contains word association data collected from native speakers, enabling exploration of how words relate in the human mind. The purpose is to provide psychologists, linguists, and neuroscientists with a resource to test theories of language representation and processing, with applications ranging from cross-cultural comparisons to language learning and retention.