To hospitalise is to admit someone to hospital for treatment — to move a patient from home or emergency care into inpatient wards where serious illness or injury can be managed. The decision follows triage: conditions too severe, unstable, or complex for outpatient care — severe infections, major trauma, acute cardiac events, complicated childbirth — require the monitoring, medication, and procedures only a hospital provides. In food-related medicine, hospitalisation follows the severe end of the spectrum: life-threatening anaphylaxis, haemolytic uraemic syndrome from E. coli, severe dehydration from food poisoning, or refeeding syndrome in malnutrition. The word marks the threshold where illness outruns what home and clinic can handle.