Co

1. company.

   the Consett Iron Co

2. county.

   Co Cork

symbol

the chemical element cobalt.

1. (forming nouns) joint; mutual; common.

   co-driver

   co-education

2. (forming adjectives) jointly; mutually.

   coequal

3. (forming verbs) together with another or others.

   co-produce

4. of the complement of an angle.

   cosine

from Latin, originally a form of com-.

1. Colorado (in official postal use).
2. Colombia (international vehicle registration).
3. Commanding Officer.
4. conscientious objector.

abbreviation, unpunctuated

care of.

noun, symbol

the chemical element of atomic number 27, a hard silvery-white magnetic metal.

late 17th century: from German Kobalt ‘imp, demon’ (because the presence of cobalt-bearing ore made it more difficult to extract silver, and miners believed that it was harmful to the silver ore with which it occurred).

1. with; together; jointly; altogether.

   combine

   command

   collude

from Latin cum ‘with’.