war plunder: the goods or people seized and carried off by force from a defeated enemy
This word names what a raiding army carries home. Sometimes that is a haul of things: livestock, silver, food, whatever can be stripped from the losing side and divided up. Other times it is the people themselves, a family, a nation, or a whole land handed over to be looted, dragged off, and left helpless. The one word covers both the loot and the losers.
Because it points to the aftermath of a defeat, it often travels in pairs with a near-twin for spoil, so a verse will speak of taking "the spoil and the plunder" together for emphasis. The prophets lean on it hard: when God warns that Israel or a foreign nation will "become plunder," the image is of a people stripped bare and carried away, a reversal of fortune that the raiders once inflicted on others now falling on them.
So the two shades are not two different words but one idea seen from two angles: the treasure that is taken, and the victims from whom it is taken.