adj. 25B6; adjective
the devious ways in which they bent the rules : UNDERHAND, deceitful, dishonest, dishonourable, unethical, unprincipled, immoral, unscrupulous, fraudulent, dubious, unfair, treacherous, duplicitous; crafty, cunning, calculating, artful, conniving, scheming, sly, wily; sneaky, furtive, secret, clandestine, surreptitious, covert; N. Amer. snide, snidey; informal crooked, shady, dirty, low-down; Brit. informal dodgy.
a devious route around the coast : CIRCUITOUS, roundabout, indirect, meandering, tortuous.