A more thorough explanation:

in plena vita (in plee-nə vI-tə), adv. & adj.[Law Latin] In full life.

In plena vita is a Latin term used in law to describe someone who is alive and well. It means that the person is in full life and not deceased or incapacitated.

• After the car accident, the doctor confirmed that the driver was in plena vita.
• The insurance policy only pays out if the policyholder dies, not if they are in plena vita.

These examples illustrate how the term is used in legal contexts to indicate that someone is alive and well. In the first example, the doctor confirms that the driver is not seriously injured and is still alive. In the second example, the insurance policy only applies in the event of the policyholder's death, not if they are still alive and healthy.