determiner

n. adjective or modifier that limits a noun (Grammar)

Determiner (function): (grammar) a function in phrase structureDeterminer (class): (grammar) a class of words (also determinative)
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Noun
1. an argument that is conclusive
(synonym) clincher, determining factor
(hypernym) argument, statement
(derivation) settle, square off, square up, determine
2. one of a limited class of noun modifiers that determine the referents of noun phrases
(synonym) determinative
(hypernym) function word, closed-class word
(hyponym) article
(derivation) specify, set, determine, fix, limit
3. a determining or causal element or factor; "education is an important determinant of one's outlook on life"
(synonym) determinant, determinative, determining factor, causal factor
(hypernym) cognitive factor
(hyponym) clincher, decisive factor
(derivation) specify, set, determine, fix, limit

v. determine, establish, fix, define, will, type, incite, calibrate, constrict, plot

(n.)
One who, or that which, determines or decides.