B.L.S. stands for Basic Life Support, which is a crucial emergency medical care method used to save the lives of people in emergencies. Some synonyms for B.L.S. include cardiopulmonary resuscitation (CPR), emergency medical care, life-saving measures, first aid, emergency response, emergency care, and medical emergency management. CPR is commonly known as an effective method used in B.L.S. to restore breathing and blood circulation in a person who has suffered cardiac arrest. First aid is the immediate care given to the injured or ill person until professional medical care is available. Emergency medical care is the medical treatment given by medical professionals in an emergency situation.