Derived from French "camarade", which was in turn derived from Latin "camara", this term means one with whom feelings of camaraderie are shared. A friend, associate, or partner can be considered a comrade. This term was, in fact, used by socialists before the Soviets popularized it, and continues to be used today by socialists, communists, and even without political connotations.
Variant of "companion" formed in England in the 1500's. It was a military (especially naval) term to address one who had achieved the same high ranking as yourself, and may only be used by commanders, admirals and such.
In the USSR it became a popular form of address, and of welcome into the social groups surrounding bolshevism.
A word used by Pavel Tsatsouline to address his butt buddies that participate in his manly kettlebell classes.
Comrade, join us over here in the jerk circle for a warm up before we do our manly kettlebell swings to tighten up our asses. Then we will proceed to the faggish get ups where we will really make a man out of you.