CO

/ˈsi ˌoʊ/

/ˈsiəʊ/

Definitions of CO

1. noun

   a state in west central United States in the Rocky Mountains
   synonyms: Centennial State, Colorado

   example of:

   American state

   one of the 50 states of the United States
2. noun

   an odorless very poisonous gas that is a product of incomplete combustion of carbon
   synonyms: carbon monoxide, carbon monoxide gas

   type of:

   monoxide

   an oxide containing just one atom of oxygen in the molecule
3. noun

   one who refuses to serve in the armed forces on grounds of conscience
   synonyms: conscientious objector

   type of:

   contestant, dissenter, dissentient, dissident, objector, protester

   a person who dissents from some established policy