Final answer:
NS stands for normal saline, which is a 0.9% solution of sodium chloride used in medical treatments, especially for intravenous infusions.
Step-by-step explanation:
The abbreviation NS stands for normal saline, which is a sterile solution of sodium chloride (NaCl) in water, used commonly in medicine. Normal saline has the same concentration of salt as the human body (0.9% NaCl), making it isotonic to bodily fluids. It is frequently used for intravenous infusions, to provide fluids and electrolytes for patients or to dilute other medications for intravenous administration.