Word abstractness has been defined in terms of hierarchical superordination or empirical ratings based on accessibility to the senses. Since a high-level superordinate (a generic term) should not be accessible to the senses, the two definitions should be correlated. Four Ss constructed word hierarchies from a pool of 925 nouns. Neither the size of a patriarch's hierarchy, nor its status as a superordinate was noticeably predictive of its abstractness rating, while its particular hierarchy membership was. The two definitions of abstractness appear to be mostly orthogonal. Subjects appear to rate the abstractness of a generic noun in terms of the abstractness of its exemplars.
ScienceDirect - Journal of Verbal Learning and Verbal Behavior : Two meanings of word abstractness