The term noninvasive can refer to diseases, procedures, or devices:

• Noninvasive diseases usually do not spread to or damage other organs and tissues.
• Noninvasive procedures do not involve tools that break the skin or physically enter the body. Examples include x-rays, a standard eye exam, CT scan, MRI, ECG, and Holter monitoring.
• Noninvasive devices include hearing aids, external splints, and casts.

Noninvasive is the opposite of invasive.