Vocabulary growth among children in a linguistically diverse community: A large-scale study

Children's vocabulary growth is linked to the quantity and quality of their language input. Thus, multilingual toddlers often have smaller vocabularies in each of their languages than monolinguals have in their one language. Could exposure to multiple accents also affect vocabulary growth? To date, no well-powered study has addressed this. Here, we compared the reported English vocabularies of three groups of 11- to 34-month-old English learners (N = 3,150; 52% female; racially diverse): bilinguals, monolinguals hearing multiple accents, and monolinguals hearing little accent variation. As expected, bilinguals had smaller English vocabularies. In contrast, monolinguals exposed to the local L1 as well as substantial non-local L1 and/or L2 accents had vocabularies similar in size to those of monolinguals receiving the local L1 accent primarily. Thus, children are well-equipped to handle accent variation in their input.