Learn what CO stands for in the context of Indian administration, and how to become a circle officer. Find out the eligibility, salary, designation, and exam pattern for this post. In conclusion, CO stands for Circle Officer, a crucial administrative and law enforcement position responsible for maintaining law and order, implementing government policies, and overseeing the overall development within a specific geographical area or circle. The full form of CO depends on its usage: most commonly, CO can stand for Carbon Monoxide (in chemistry and science), Commanding Officer (in the army, police, and defence services), and Company (in business and official documents). Learn the different meanings of CO in company, chemistry, army, police, education, medical billing, and NCC. CO can stand for Corporation, Carbon Monoxide, Commanding Officer, Circle Officer, Contractual Obligation, and more.