Determinative

a.	1.	Having power to determine; limiting; shaping; directing; conclusive. Incidents . . . determinative of their course. - I. Taylor. Determinative tables (Nat. Hist.) tables presenting the specific character of minerals, plants, etc., to assist in determining the species to which a specimen belongs.
n.	1.	That which serves to determine. Explanatory determinatives . . . were placed after words phonetically expressed, in order to serve as an aid to the reader in determining the meaning. - I. Taylor (The Alphabet).

Noun	1.	determinative - one of a limited class of noun modifiers that determine the referents of noun phrases Synonyms: determiner
	2.	determinative - a determining or causal element or factor; "education is an important determinant of one's outlook on life" Synonyms: causal factor, determinant, determining factor, determiner
Adj.	1.	determinative - having the power or quality of deciding; "the crucial experiment"; "cast the deciding vote"; "the determinative (or determinant) battle" Synonyms: deciding, determinant, determining, crucial

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