comrade

kamrat

1. A companion in battle; fellow soldier.

2. A mate, companion, or associate. [from 1590s]

3. (communism, by extension) A fellow socialist, communist or other similarly politically aligned person. [from 1884]

4. (communism) A non-hierarchical title, functionally similar to "Mr.", "Mrs.", "Miss", "Ms." etc, in a communist, socialist, or rarely in an Islamist state. [from 1884]