" double-dealer "

1: one who betrays a trust or an allegiance;

  * e.g., " ... the company seems to have one or two double-dealers who are selling information to competitors "

•  Synonyms : 

•  apostate,

•  backstabber,

•  betrayer,

•  double-crosser,

•  Judas,

•  quisling,

•  recreant,

•  serpent,

•  snake,

•  traitor,

•  turncoat

•  Antonyms : 

• (N/A)

1: the inclination or practice of misleading others through lies or trickery;

  * e.g., " ... a go-between suspected of double-dealing "

•  Synonyms : 

•  artifice,

•  cheating,

•  cozenage,

•  craft,

•  craftiness,

•  crookedness,

•  crookery,

•  cunning,

•  cunningness,

•  deceit,

•  deceitfulness,

•  deception,

•  deceptiveness,

•  dishonesty,

•  dissembling,

•  dissimulation,

•  dupery,

•  duplicity,

•  fakery,

•  foxiness,

•  fraud,

•  guile,

•  guilefulness,

•  wiliness

•  Antonyms : 

•  artlessness,

•  forthrightness,

•  good faith,

•  guilelessness,

•  ingenuousness,

•  sincerity