knotty

adjectives

making great mental demands; hard to comprehend or solve or believe
"a baffling problem"; "I faced the knotty problem of what to have for breakfast"; "a problematic situation at home"
is derived from
used of old persons or old trees; covered with knobs or knots
"gnarled and knotted hands"; "a knobbed stick"
highly complex or intricate and occasionally devious
"the Byzantine tax structure"; "Byzantine methods for holding on to his chairmanship"; "convoluted legal language"; "convoluted reasoning"; "the plot was too involved"; "a knotty problem"; "got his way by labyrinthine maneuvering"; "Oh, what a tangled web we weave"- Sir Walter Scott; "tortuous legal procedures"; "tortuous negotiations lasting for months"
is derived from
tangled in knots or snarls
"a mass of knotted string"; "snarled thread"
is derived from
is derived from