Reverse Dictionary: TREACHEROUS

ADJECTIVES
► BREAK-FAITH perfidious, treacherous → 1911 Sc. (Bk.)
► CROCODILIAN making a hypocritical show of grief; cruel and treacherous; deceitful → 1632 obs.
► CULVERT infamous, villainous, treacherous → c1225 obs.
► FAITEROUS characterized by deceit; treacherous → 1600 obs.
► FELL-LURKING cruel and treacherous, lurking to do mischief → 1908  (Bk.)
► FICKLE  unsteady, unsafe; treacherous → 1812 Sc.
► GINFUL ingenious; crafty, guileful; deceitful, treacherous → c1300 obs.
► GLIDDERY treacherous → 1869 Eng. dial.
► HECTIC fairly treacherous → 1988 US sl.
► JUDAS-LIKE traitorous, treacherous; resembling Judas Iscariot → 1577
► LEWE treacherous → c1000 obs.
► MICHING treacherous, untrustworthy → 1905 Eng. dial. (Bk.)
► NAR treacherous → 1988 US sl.
► PERFIDIOUS guilty of breaking faith or violating confidence; deliberately faithless; treacherous; deceitful and untrustworthy → 1538
► PRODITORIOUS treacherous, traitorous, perfidious; apt to betray or reveal what is hidden or in the mind; apt to disclose or make known → c1475 obs.
► SNAKY guileful, deceitful, treacherous → a1586
► SWIKE deceitful; treacherous; traitorous → c1175 obs.
► SWIKEFUL deceitful, treacherous → c1100 obs. exc. Sc.
► SWIKEL deceitful, treacherous, crafty → c1000 obs.
► TEPTIOUS snappish, captious; irritating; treacherous, changeable, not to be depended upon → 1876 Eng. dial.
► UNDERMINDED sly, deceptive, double-faced; underhand, mean, treacherous → 1902 Eng. & Amer. dial.
► UNDERNEAN deceitful, treacherous, underhand → 1905 Eng. dial. (Bk.)

ADVERBS
► JUDAS-LIKE traitorously, treacherously → 1569
► JUDASLY in the manner of Judas Iscariot; traitorously; with terrible treachery or betrayal → 1508
► SUBTLY with craft or guile; craftily, treacherously, deceitfully, insidiously → c1325 obs.
► SWIKELLY deceitfully, treacherously → a1023 obs.
► SWIKINGLY treacherously → c1175 obs.

NOUNS
► BETRAY a treacherous giving up to an enemy; betrayal → 1600 obs.
► COVIN fraudulent action of any kind to the injury of another; fraud, deceit, treachery → 1487 arch.
► CRAP treachery → 1914 criminals’ sl. (Bk.)
► CULVERTSHIP villainy, treachery, perfidy → a1250 obs.
► DOG’S TRICK a low or despicable trick; a treacherous or spiteful act; a bad turn → 1742
► DOUBLENESS duplicity, deceitfulness, treachery → c1374
► FALSE fraud, falsehood, treachery; in early use, counterfeiting of coin; forgery → c1000 obs.
► FALSEDOM treachery; untruth; a falsehood → 1297 obs.
► FALSE PLAY treacherous dealing → 1567 obs.
► FALSET falsehood, treachery, fraud → 1375 obs., chiefly Sc.
► FALSITY false or treacherous conduct; treachery, fraud → c1330 obs.
► FELLNESS treachery, deceitfulness; craftiness → a1398 obs.
► GREEK GIFT a gift covering some act of treachery → 1885
► HOOK, THE an instance of treachery; a double cross → 1908 Amer. sl.
► PERFIDITY deceitfulness, untrustworthiness; betrayal of trust; breach of a promise; treachery → 1607
► PERFIDY deceitfulness, untrustworthiness; betrayal of trust; breach of a promise; treachery → 1592
► PUNIC FAITH treachery, faithlessness; bad faith → 1590
► SINONISM a trick, deception; a treacherous act → 1864
► SWIKE deceit, deception, treachery; a trick → c893 obs. exc. Eng. dial.
► SWIKEDOM deceit, fraud; treachery, treason → c893 obs.
► SWIKEHEAD deceit, fraud; treachery, treason → a1250 obs.
► SWIKELNESS deceitfulness, treachery → a1023 obs.
► TWIST, THE cheating, dishonesty; treachery → 1933 criminals’ sl.
► UNTROTH unfaithfulness, treachery → 1374 obs.

NOUNS – PERSON
► ACHITOPHEL a treacherous friend and adviser an able but unprincipled counsellor → 1903 (Bk.)
► ADDER a treacherous, deceitful, malicious, or pernicious person or thing; also, a term of abuse → c1000
► BAD MEMBER a doer of evil; a bad character; a treacherous fellow → 1910 Ireland (Bk.)
► BEYOTCH a malicious or treacherous woman; a ‘bitch’ → 1986 US sl., derogatory & offensive
► BIATCH applied opprobriously to a woman; a malicious or treacherous woman; a bitch → 1986 orig. & chiefly US sl., derogatory & offensive
► BITCH a term of abuse for a woman; strictly, a lewd or sensual woman; later, a malicious, treacherous, unpleasant, or otherwise despicable woman → a1400
► COCKATRICE a malicious, treacherous, or destructive person → 1508
► COPPERHEAD any treacherous person → US Civil War usage
► COPPER HEART a treacherous person → 1942 Amer. sl. (Bk.)
► DELILAH a temptress; a seductive and treacherous woman → L16
► DINGO a cowardly, treacherous, or despicable person → 1869 Aust. sl.
► DOG a treacherous or brutal person → 1966 US sl., esp. African-American
► EEL an elusive, shrewd, sly, or deceptive person; a treacherous person → 1933 Amer. dial., usually derogatory
► FELLOW TRAVELER a person working secretly for a foreign government; a treacherous person → World War II Amer. sl.
► GONSEL ► GONSIL ► GUNSIL ► GUNTZEL a treacherous person → 1942 Amer. sl. (Bk.)
► HIGH-GRADER a treacherous person → 1942 Amer. sl. (Bk.)
► JUDAS JEW a person whose treachery resembles that of Judas; later, a Jewish person likened to Judas in having committed an act of betrayal, disloyalty, etc. → 1633 offensive
► MINK a treacherous person → Bk1913-17 Amer. dial.
► MUZZLER a treacherous person → 1942 Amer. sl. (Bk.)
► NIGHT-WORM a treacherous comrade → 1430-40 obs.
► NONTRUST a treacherous person → 1942 Amer. sl. (Bk.)
► SCALY-BACK a treacherous, untrustworthy person → 20C Brit. sl.
► SCALY-BACKED REPTILE a treacherous, untrustworthy person → 20C Brit. sl. 
► SPLIT CASE a treacherous person → 1942 Amer. sl. (Bk.)
► TIGRESS a treacherous person → Bk1913-17 Amer. dial.
► TWO-WAY GUY a treacherous person → 1942 Amer. sl. (Bk.)
► WRONG GUY a treacherous person → 1942 Amer. sl. (Bk.)

VERBS
► BETRAISE ► BETRAISH to be a traitor to; to be treacherous; to deceive the trustful or innocent → c1374 obs.
► COME THE DOUBLE to act in a treacherous or evasive manner → 1888 sl.
► DECEIVE to be or prove false to, to play false, to deal treacherously with; to betray → a1300 obs.
► DINGO to behave in a treacherous or cowardly manner → 1935 Aust. sl.