A key aspect of understanding how children learn the meanings of words involves understanding how they mine different sources of information (e.g., observational, linguistic) in the service of learning. According to one dominant view, there exists a class of words (i.e., “hard words”; Gleitman et al., 2005) for which learning their meaning requires access to information beyond the observational contexts in which those words occur. Building upon previous work on this topic that employed the Human Simulation Paradigm, a paradigm commonly used for investigating vocabulary learning, the current study revisits the role of observational contexts for the acquisition of one class of hard words: nouns that denote non-basic level object categories (or “hard nouns”; see Kako, 2005). These data reveal that although observational contexts may not be sufficient to yield learning of precise hard noun meanings, they allow learners to extract systematic partial knowledge, knowledge that may lay a critical foundation for meaning acquisition.

Children learn words that name objects (“ball”) and those that name abstract concepts (“story”). One view of learning is that different inputs matter for different words (Snedeker & Gleitman, 2004). That is, many argue that although the observational contexts in which words occur are sufficient for learning object names, they are not for learning abstract “hard words” (Gleitman et al., 2005). This study revisited the contributions of observational contexts to learning one type of hard word: nouns denoting non-basic level object categories (“hard nouns” like “friend”; Kako, 2005). In a new artificial learning paradigm, we reveal that although observational contexts were insufficient for full hard noun learning, they afforded learners partial knowledge that allowed them to succeed in some learning tasks. These data highlight how observational contexts may lay the foundation for learning hard nouns, and underscore how definitions of learning impact our understanding of how the input shapes it.