1. having the most thorns; most prickly
Usage: superlative form of thorny
2. most difficult, complicated, or problematic
Usage: figurative use

Examples

• The thorniest rose bush in the garden required thick gloves to prune.
• This is the thorniest issue facing the committee this year.
• She tackled the thorniest problems first to get them out of the way.
• The thorniest part of the negotiation involved salary discussions.
• Even the thorniest blackberry canes couldn’t stop the determined hikers.
• The thorniest questions on the exam were worth the most points.