A path with a confusing proliferation of turns is tortuous (from a French root meaning “twisted”). But “torturous” (meaning painful or unpleasant, like torture) is very frequently confused with it. So often has “tortuous logic” (tangled, twisted logic) been misspelled as “torturous logic” that it has given rise to a now independent form with its own meaning, “tortured logic.” Few people object to the latter, but if you want to describe your slow progress along a twisting path, the word you want is “tortuous.”
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