deceitful

adjectives

intended to deceive
"deceitful advertising"; "fallacious testimony"; "smooth, shining, and deceitful as thin ice" - S.T.Coleridge; "a fraudulent scheme to escape paying taxes"
deceitful, fallacious, fraudulent
is derived from
deceitfulness
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
Janus-faced, ambidextrous, deceitful, double-dealing, double-faced, double-tongued, duplicitous, two-faced
is derived from
deceitfulness