'Troops' in the Bible

The number of the troops of cavalry was twice ten thousand times ten thousand (two hundred million); I heard the number of them.

And the armies of heaven, dressed in fine linen, [dazzling] white and clean, followed Him on white horses.

Then I saw the beast and the kings and political leaders of the earth with their armies gathered to make war against Him who is mounted on the [white] horse and against His army.