Final answer:
The term for cells that grow uncontrolled and invade normal tissues is cancer. Cancer cells can form tumors that may invade surrounding tissues and spread to other parts of the body.
Step-by-step explanation:
The term that refers to cells that are not confined in their growth and invade normal tissues is cancer. Cancer cells display uncontrolled growth and disregard the regulatory mechanisms that typically limit cell division and maintain tissue organization. These cells can form tumors which may be benign, meaning they remain localized, or malignant, meaning they invade surrounding tissues and, potentially, metastasize to distant sites in the body. Malignant tumors are characterized by their ability to spread to other organs, a process that complicates treatment and can lead to serious health consequences.