Source : Webster's Revised Unabridged Dictionary (1913)

Smooth-spoken \Smooth"-spo`ken\, a.
   Speaking smoothly; plausible; flattering; smooth-tongued.

Source : WordNet®

smooth-spoken
     adj : expressing yourself readily, clearly, effectively; "able to
           dazzle with his facile tongue"; "silver speech" [syn: {eloquent},
            {facile}, {fluent}, {silver}, {silver-tongued}]