There are a couple of acronyms for fear: False Expectations Appearing Real or Failure Expected And Received.
A more formal definition would be the anticipation of pain.
This definition illustrates the fact that fear is about the FUTURE. Can we live in the future? No, but our mind sure spends a lot of time there. It’s busy making up scenarios of what will happen if you do this thing you fear. And they’re always elaborate and a little crazy, just like a soap opera.