A more thorough explanation:

Definition: Harmful; tending to injure.

Examples:

• The chemicals in the cleaning product were injurious to my skin.
• Excessive alcohol consumption can be injurious to your health.
• Using your phone while driving is not only illegal but also injurious to yourself and others on the road.

The examples illustrate how something can be injurious if it causes harm or injury. In the first example, the chemicals in the cleaning product caused harm to the person's skin. In the second example, excessive alcohol consumption can cause harm to a person's health. In the third example, using a phone while driving can cause harm to oneself and others on the road.