High Quality Content by WIKIPEDIA articles! In medicine, saline (also saline solution) is a general term referring to a sterile solution of sodium chloride (NaCl, more commonly known as salt) in water but is only sterile when it is placed intravenously, otherwise, a saline solution is a salt water solution. The sterile solution is typically used for intravenous infusion, rinsing contact lenses, nasal irrigation, and often used to clean a new piercing. Saline solutions are available in various formulations for different purposes. Salines are also used in cell biology, molecular biology, and biochemistry experiments.