This study examined the receptive language skills of young children (4-6 years old) with specific language impairment (SLI). Specifically, the authors looked at their ability to fast-map semantic features of objects and actions and compared it to the performance of age-matched peers with normally developing language (NL). Children completed a computer task during which they were exposed to novel objects and actions with novel names. The children then were asked questions about the semantic features of these novel objects and actions. Overall, the questions about actions were more difficult for children than objects. The children with SLI were able to recognize fewer semantic features than were their peers with NL. They also performed poorly relative to their peers on a lexical label recognition task. These results lend support to the idea that children with SLI have brooder difficulties with receptive vocabulary than simply a reduced ability to acquire labels.KEY WORDS: semantics, receptive language, specific language impairment (SLI), children, word learning