1. not based on or guided by reason or logical thinking

Examples

• She felt an unreasoning fear of the dark basement.
• His unreasoning hatred of change made him difficult to work with.
• The crowd’s unreasoning panic led to chaos at the exit.
• An unreasoning loyalty to the company cost him better opportunities.
• The child’s unreasoning terror of dogs stemmed from an early incident.
• Her unreasoning optimism helped her through difficult times.