Webster’s Revised Unabridged Dictionary · 1913
Determinative
De·ter′mi·na·tive (dē·tẽr′mĭ·nȧ·tĭv), a. [Cf. F. déterminatif.] 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.
De·ter′mi·na·tive (dē·tẽr′mĭ·nȧ·tĭv), n. 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).