[Inferring the meaning of a novel adjective by Japanese preschoolers].

This study examined how Japanese preschoolers infer the meaning of a novel adjective and noun. The participants, 41 three-year-olds and 44 four-year-olds, were introduced to a novel adjective or a novel noun in association with a familiar object. They were then shown five test objects and asked to choose all the objects to which they could apply the novel word. The results indicated that although both three- and four-year-olds tried to extend adjectives using a different principle from nouns, only four-year-olds successfully extended a novel adjective based on the sameness of property. Three-year-olds seem to have trouble extracting a common property across objects especially when those objects belong to different basic-level categories.