Source : Webster's Revised Unabridged Dictionary (1913)

Subordinative \Sub*or"di*na*tive\, a.
   Tending to subordinate; expressing subordination; used to
   introduce a subordinate sentence; as, a subordinative
   conjunction.

Source : WordNet®

subordinative
     adj : serving to connect a subordinate clause to a main clause;
           "`when' in `I will come when I can' is a subordinating
           conjunction" [syn: {subordinating(a)}] [ant: {coordinating(a)}]