Final answer:
An outpatient or ambulatory surgery refers to a procedure where the patient can leave the facility on the same day, without the need for an overnight stay.
Step-by-step explanation:
A surgical procedure that allows a patient to walk in and walk out of the facility the same day is called an outpatient surgery or ambulatory surgery. These procedures are designed to be less invasive, allowing for a quicker recovery time and thus do not require an overnight stay in the hospital. Examples might include arthroscopic surgeries or minor cosmetic surgeries. This type of medical care is increasingly popular as it tends to be more convenient and cost-effective for both the patient and the healthcare provider.