1.
Something big, hairy, and scary. (No, dude, not your penis...I said big :-) ) that can ACTUALLY happen to you, as opposed to an
irrational fear.
2. Something not physically scary, but mentally
terrifying yet very real...like an "aw, shit" moment.
Examples of rational fears:
That 90 pound
Rottweiler that's about to latch onto your ass like it was a big, meaty, steak.
That 15-year
old girl's father after he found out you were studying anatomy instead of geometry.
Worrying that you're gonna
flunk geometry because you were studying anatomy instead of geometry.