1 dread, terror, fright, panic, horror, alarm, trepidation, apprehension, fearfulness, apprehensiveness, dismay, consternation, hesitation, qualms, diffidence, timidity, cravenness, cowardice, second thoughts:
His fear of going into the jungle alone is understandable.
2 awe, respect, reverence, veneration:
That'll put the fear of God into him!
3 horror, spectre, nightmare, bogey or bogy, phobia, bugbear, bête noire, misgiving(s), foreboding(s):
When they came to break the news, her worst fears were realized.
4 solicitude, anxiety, angst, foreboding(s), distress, misgiving(s), concern, apprehension, worry, uneasiness, unease:
Fear for her safety is shared by all of us.
5 be afraid or scared or fearful or frightened (of), dread, quail or tremble or quake at, shudder at, shrink from, quiver:
What man cannot understand he often fears.
6 revere, respect, venerate, be or stand in awe of:
If you fear the Lord as I do, you won't take his name in vain.
7 expect, anticipate, imagine, suspect, foresee:
I fear we are too late for dinner.