Abstract
All words are learned. The only source of words for children acquiring a language is the surrounding social environment. How many and which words children learn depend crucially on how many and which words they encounter. Bilinguals are prone to have smaller vocabularies (in one language) compared to monolinguals since their immersion in a language is split between the two systems. This may lead to an incorrect diagnosis of language disorder in bilingual children, since children with Specific Language Impairment (SLI) are usually late talkers and lag behind typically developing children with respect to vocabulary size during preschool. On the other hand, bilingual children with a language disorder also run the risk of not being diagnosed, since a smaller vocabulary is expected in a bilingual child. Thus, an accurate assessment of vocabulary size of bilingual children in both of their languages is needed to differentiate between children with typical, balanced language development (similar vocabulary size in both languages, smaller than in monolingual children but typical of bilingual ones), unbalanced language development (significantly smaller vocabulary in one language only, but typical of bilinguals in the other one) and suppressed vocabulary in both languages (suggesting a risk for SLI). [...]
This is an accepted version of an article published in Clinical Linguistics & Phonetics. © 2017 Taylor & Francis