1. (adjective) making great mental demands; hard to comprehend or solve or believe

• baffling
• elusive
• problematic
• problematical
• tough

2. (adjective) used of old persons or old trees; covered with knobs or knots

• gnarled
• gnarly
• knobbed
• knotted

3. (adjective) highly complex or intricate and occasionally devious

• byzantine
• convoluted
• involved
• tangled
• tortuous

4. (adjective) tangled in knots or snarls

• snarled
• snarly

1. (adjective) making great mental demands; hard to comprehend or solve or believe

• difficult
• hard

2. (adjective) used of old persons or old trees; covered with knobs or knots

• crooked

3. (adjective) highly complex or intricate and occasionally devious

• complex

4. (adjective) tangled in knots or snarls

• tangled

1. (adjective) making great mental demands; hard to comprehend or solve or believe

• complicatedness
• complication
• knottiness
• tortuousness
• formidability
• toughness
• job
• job
• problem
• problem

2. (adjective) used of old persons or old trees; covered with knobs or knots

• gnarl
• knot

3. (adjective) highly complex or intricate and occasionally devious

• complicatedness
• complicatedness
• complication
• complication
• knottiness
• knottiness
• tortuousness
• tortuousness

4. (adjective) tangled in knots or snarls

• gnarl
• knot
• knot
• maze
• snarl
• tangle