1. the class of all items that can be substituted into the same position (or slot) in a grammatical sentence (are in paradigmatic relation with one another); [syn: substitution class, paradigm]
WordNet (r) 3.0 (2006):
substitution class
n 1: the class of all items that can be substituted into the
same position (or slot) in a grammatical sentence (are in
paradigmatic relation with one another) [syn: substitution
class, paradigm]