determiner

Short definition from Wiktionary

Noun

1. 1
   Someone or something that determines, or helps to determine, something else: A factor that defines something, or one among several that define it.
2. 2
   Someone or something that determines, or helps to determine, something else: Someone or something (especially a sentient agent) that determines; a decider of a disposition.
3. 3
   A member of a class of words functioning in a noun phrase to identify or distinguish a referent without describing or modifying it.
4. 4
   A dependent function in a noun phrase that marks it as definite or indefinite. This function is usually filled by words in the determinative class but may be filled by other elements such as a genitive pronoun.