CO — synonyms, definition

1. CO (Noun)

Centennial State atomic number 27 carbon monoxide carbon monoxide gas cobalt colorado conscientious objector

CO (Noun) — An odourless very poisonous gas that is a product of incomplete combustion of carbon.

CO (Noun) — A state in west central United States in the Rocky Mountains.

CO (Noun) — One who refuses to serve in the armed forces on grounds of conscience.

CO (Noun) — A hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition.

American state contestant dissenter dissident metal metallic element monoxide objector protester protestor cobalt 60 Arkansas Arkansas River Colorado Plateau Colorado River Colorado Springs Denver Mesa Verde National Park Mile-High City Mount Sherman North Platte North Platte River Pike's Peak Republican Republican River Rocky Mountain National Park San Juan Mountains Sherman South Platte South Platte River boulder • • • America U.S. U.S.A. USA United States United States of America cobaltite smaltite the States us

2. CO (Prefix)

CO (Prefix) — Together, with, joint.

3. CO (Preposition)

CO (Preposition) — (mail) to be delivered to (e.g. the address of someone who will then give the delivery to the intended recipient). ex. "Please mail this to John, c/o his mother"