'Signs' in the Bible

Then Caleb made signs to the people to keep quiet, and said to Moses, Let us go up straight away and take this land; for we are well able to overcome it.

And Joshua, the son of Nun, and Caleb, the son of Jephunneh, two of those who had been to see the land, giving signs of grief,

And the Lord said to Moses, How long will this people have no respect for me? how long will they be without faith, in the face of all the signs I have done among them?

Because all these men, having seen my glory and the signs which I have done in Egypt and in the waste land, still have put me to the test ten times, and have not given ear to my voice;