The Collaborative International Dictionary of English v.0.48:

Deprecative \Dep"re*ca*tive\ (d[e^]p"r[-e]*k[asl]*t[i^]v), a.
   [L. deprecativus: cf. F. d['e]pr['e]catif.]
   Serving to deprecate; deprecatory.
   [1913 Webster]

   Syn: belittling, derogatory, pejorative, disparaging,
        depreciative, deprecatory, depreciatory, detractive,
        detracting, slighting, denigratory, uncomplimentary.
        [PJC] -- Dep"re*ca*tive*ly, adv.
        [1913 Webster]

WordNet (r) 3.0 (2006):

deprecatively
    adv 1: in a deprecative manner