Diversity in Monolingual and Multilingual Communicative Environments and its Relation to Vocabulary in Early Childhood

Research on multilingualism often assumes homogeneity within monolingual andmultilingual groups, overlooking diversity in language environments, such as differences inlanguage exposure and combinations. This study examines three such diversity indicators—language entropy, context entropy, and linguistic distance—and their relationship tovocabulary in 4- to 5-year-old mono- and multilingual children (N = 257). Results revealsignificantly greater vocabulary in monolinguals than multilinguals when comparing onelanguage, but multilinguals outperform monolinguals on conceptual vocabulary. Vocabularysize in multilinguals showed a quadratic relationship with language and context entropy,initially increasing but declining at higher entropy levels. Additionally, children with greaterlinguistic distances generally had larger dominant vocabularies. However, within the groupwith high linguistic distance, further increased distance was linked to smaller dominantvocabularies. These findings suggest that the applied diversity indicators capture meaningfulvariation in language environments, offering valuable insights about diversity inenvironments on vocabulary outcomes in multilingual children.