knotty

Meanings

• making great mental demands; hard to comprehend or solve or believe
  • "I faced the knotty problem of what to have for breakfast"
• used of old persons or old trees; covered with knobs or knots
• highly complex or intricate and occasionally devious; ; ; ; ; ; ; ; - Sir Walter Scott
  • "a knotty problem"
• tangled in knots or snarls

Synonyms

baffling, Byzantine, convoluted, elusive, gnarled, gnarly, involved, knobbed, knotted, problematic, problematical, snarled, snarly, tangled, tortuous, tough