'Watcher' in the Bible

If I have sinned, what have I done to You,Watcher of mankind?Why have You made me Your target,so that I have become a burden to You?

I saw in the visions of my head upon my bed, and, behold, a watcher and an holy one came down from heaven;

And whereas the king saw a watcher and an holy one coming down from heaven, and saying, Hew the tree down, and destroy it; yet leave the stump of the roots thereof in the earth, even with a band of iron and brass, in the tender grass of the field; and let it be wet with the dew of heaven, and let his portion be with the beasts of the field, till seven times pass over him;