Literary or formal term for a person who is shrewd in a deceitful or underhanded way. Often implies a negative moral judgment.
He used cunning methods to bring down his rivals.
奸黠な笑みを浮かべて、彼は取引を持ちかけた。
With a sly grin, he proposed the deal.
Standard kanji form; 奸 carries a nuance of wickedness or deceit.
Variant using 姦, which also suggests wickedness or adultery; less common than 奸黠.
Compound of 奸 (wicked, deceitful) and 黠 (crafty, cunning). The exact historical derivation is uncertain, but the combination has been used in classical Chinese and later in Japanese literary contexts to describe a shrewd and morally questionable person.