'Watcher' in the Bible

“Have I sinned? What have I done to You,O watcher of men?Why have You set me as Your target,So that I am a burden to myself?

‘I was looking in the visions in my mind as I lay on my bed, and behold, an angelic watcher, a holy one, descended from heaven.

In that the king saw an angelic watcher, a holy one, descending from heaven and saying, “Chop down the tree and destroy it; yet leave the stump with its roots in the ground, but with a band of iron and bronze around it in the new grass of the field, and let him be drenched with the dew of heaven, and let him share with the beasts of the field until seven periods of time pass over him,”