A state of unpleasant arousal in situations of real threat (as opposed to anxiety, which generally occurs without the presence of any external stimulus).
Example: A soldier is pinned down by heavy fire; his ammunition is expended and all his friends are dead or wounded. He trembles with dread.
Grinnell, R. (2016). Fear. Psych Central. Retrieved on May 19, 2017, from https://psychcentral.com/encyclopedia/fear/