'Signs' in the Bible

We made music for you and you did not take part in the dance; we gave cries of sorrow and you made no signs of grief.

And in the morning, It will be foul weather to day: for the sky is red and lowring. O ye hypocrites, ye can discern the face of the sky; but can ye not discern the signs of the times?

You know how to interpret the appearance of the sky, yet you can't interpret the signs of the times? An evil and adulterous generation craves a sign, but no sign will be given to it except the sign of Jonah." Then he left them and went away.

For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect.

so you, too, when you see all these things [taking place], know for certain that He is near, right at the door.