A determiner is an item that combines with the noun and specifies its referentiality, i.e. the relation between the noun and what the noun refers to (PRAGMATICS 1). Specifically, it indicates whether the noun refers to a definite or indefinite element of a class. For this reason, determiners are usually categorised into two classes: definite (LEXICON 3.6.1) and indefinite (LEXICON 3.6.2).
The term determiners is intended here to include both articles and demonstratives. The syntactic distribution of determiners in LIS is addressed in SYNTAX 4.1.