Final answer:
A blood sample collected 2 hours after a meal is called a postprandial blood sample (PP). It is used to measure blood glucose levels after a meal to assess how well the body is able to metabolize glucose.
Step-by-step explanation:
The blood sample collected 2 hours after the patient has ingested a meal is called a postprandial blood sample (PP). PP stands for postprandial, which means 'after a meal' in Latin. It is used to measure blood glucose levels after a meal to assess how well the body is able to metabolize glucose.