'Man's' in the Bible

See, I am waiting at the door and giving the sign; if my voice comes to any man's ears and he makes the door open, I will come in to him, and will take food with him and he with me.

The first living creature was like a lion, the second creature like an ox, the third creature had a face like a man's, and the fourth creature looked like an eagle flying.

Here is wisdom. He that has understanding let him count the number of the beast: for it is a man's number; and its number is six hundred and sixty-six.

The second poured out his bowl into the sea. It turned to blood like a dead man’s, and all life in the sea died.

And he measured its wall, a hundred and forty-four cubits, a man's measure, that is, the angel's.