double-tongued

from WordNet (r) 3.0 (2006)

double-tongued
    adj 1: marked by deliberate deceptiveness especially by
           pretending one set of feelings and acting under the
           influence of another; "she was a deceitful scheming
           little thing"- Israel Zangwill; "a double-dealing double
           agent"; "a double-faced infernal traitor and schemer"-
           W.M.Thackeray [syn: {ambidextrous}, {deceitful}, {double-
           dealing}, {duplicitous}, {Janus-faced}, {two-faced},
           {double-faced}, {double-tongued}]

from The Collaborative International Dictionary of English v.0.48

Double-tongued \Dou"ble-tongued`\, a.
   Making contrary declarations on the same subject; deceitful.

   Syn: deceitful, double-faced, hypocritical, Janus-faced,
        two-faced.
        [1913 Webster]

              Likewise must the deacons be grave, not
              double-tongued.                     --1 Tim. iii.
                                                  8.
        [1913 Webster]