'Signs' in the Bible

And God said, Let there be lights in the arch of heaven, for a division between the day and the night, and let them be for signs, and for marking the changes of the year, and for days and for years:

And Laban said, If you will let me say so, do not go away; for I have seen by the signs that the Lord has been good to me because of you.

Now when Reuben came back to the hole, Joseph was not there; and giving signs of grief,

Then Jacob, giving signs of grief, put on haircloth, and went on weeping for his son day after day.