Word learning implies learning of both a phonological form and its referent. For nouns, the referent is typically a category of objects, with variability between objects within the category but an overlying similarity that allows them to be categorized together, to function similarly, and to be called by the same label. We hypothesized that by strengthening knowledge of the category of referents a word refers to, we could strengthen learning and use of the word.

Three-year old children were provided with elaborated referent category information in the form of multiple exemplars of the referent category. In the first manipulation, children were trained on identical exemplars or variable exemplars. A second manipulation provided children with variable exemplars that had been distributed to support a prototype. Children in the third condition, who were provided with a prototype plus variants, learned words best in expressive and receptive tasks, when tested on trained and untrained items, and at two time points. In a second manipulation, we asked if simultaneous presentation of multiple exemplars leads to better learning of the object label than sequential presentation. Results indicated little difference. We conclude that 3-year-olds learn words best in the presence of variability distributed to highlight both invariant elements of the referent category and those elements that are allowed to vary.