Final answer:
The medical abbreviation for nothing by mouth or withhold food, water, oral medications is NPO.
Step-by-step explanation:
The medical abbreviation for nothing by mouth or withhold food, water, oral medications is NPO. It stands for 'nil per os', which is Latin for 'nothing by mouth'. This abbreviation is commonly used in healthcare settings to indicate that a patient should not consume any food, liquids, or medications orally for a specified period of time.