co
1. With; together; joint; jointly
2. In or to the same degree
3. One that is associated in an action with another; fellow; partner; having a usually lesser share in duty or responsibility; alternate; deputy
4. Of, relating to, or constituting the complement of an angle
CO · Centennial State · Colorado · atomic number 27 · carbon monoxide · carbon monoxide gas · cobalt · conscientious objector