You are right that the word has many meanings. The one that was used in the documentary in "they charged to the parapet" is a verb meaning to run towards something with an intent to damage it or overthrow it. For example, we often would describe a bull as "charging" at a bullfighter. It can also be used as a noun, describing the action. For example, the Red army made a charge at the Blue army. It would also be used as a command in war, telling the soldier to charge at the enemy --- "ready, set, charge!!!"
Also, the first sentence of your post used the incorrect spelling of "bare". This word means naked or without covering, as in a bald man's head being called bare. The correct word to use is pronounced the same, but spelled "bear".
So, it should be:
This is one of those words that seem to bear within their letters the weight of a thousand different meanings.