1. causing harm or damage; having a harmful effect
Usage: formal

Examples

• Smoking has deleterious effects on your health.
• The factory’s pollution had a deleterious impact on the local environment.
• Too much screen time can be deleterious to children’s sleep patterns.
• The new policy proved deleterious to employee morale.
• Excessive stress has deleterious consequences for both mental and physical well-being.
• The drought had deleterious effects on crop yields throughout the region.