The Collaborative International Dictionary of English v.0.48:

Insinuative \In*sin"u*a*tive\, a. [Cf. F. insinuatif.]
   [1913 Webster]
   1. Stealing on or into the confidence or affections; having
      power to gain favor. "Crafty, insinuative, plausible men."
      --Bp. Reynolds.
      [1913 Webster]

   2. Using insinuations; giving hints; insinuating; as,
      insinuative remark.
      [1913 Webster]