1. Making great mental demands; hard to comprehend or solve or believe
   "I faced the knotty problem of what to have for breakfast"
   - baffling, elusive, problematic, problematical, tough 
2. Used of old persons or old trees; covered with knobs or knots
   - gnarled, gnarly, knotted, knobbed 
3. Highly complex or intricate and occasionally devious
   "a knotty problem"
   - Byzantine, convoluted, involved, tangled, tortuous 
4. Tangled in knots or snarls
   - snarled, snarly

Derived forms: knottier, knottiest

See also: complex, crooked, difficult, hard, knot, knottiness, tangled

Encyclopedia: Knotty

• pull ahead
• pull along
• pull at
• pull away
• pull chain
• pull down
• pull in one's horns
• pull off
• pull one's weight
• pull out all the stops
• pull round
• pull someone's leg
• pull strings
• pull tab
• pull the leg of
• pull the plug
• pull the wool over someone's eyes
• pull together
• pull up
• pull up short
• pull up stakes
• pull wires
• pull-in
• pull-through
• pullback