Previous work has found that shy children show chance-level disambiguation and retention of novel word meanings in a typical lab-based word learning task. This effect could be explained in terms of shy children's aversion to unfamiliarity disrupting the requisite attentional processes, because the task is marked by a high degree of unfamiliarity. To test this argument, we examined whether increasing the familiarity of the task facilitates shy children's ability to form and retain word meanings. Two-year-old children (N=23) took part in a word learning task in which their caregiver acted as the experimenter. On referent selection trials, children were presented with sets of three objects, one novel and two familiar, and were asked for either a familiar object using its known label, or a novel object using a novel word. Children were then tested on their retention of the previously formed novel word-object mappings. In this context of increased familiarity, shyness was unrelated to performance on referent selection trials. However, shyness was positively related to children's retention of the word-object mappings, meaning that shyer children outperformed less-shy children on this measure of word learning. These findings show that context-based familiarity interacts with intrinsic individual differences to affect word learning performance.