You searched for: “batophobia
batophobia (s) (noun), batophobias (pl)
An abnormal fear of passing or walking close to high objects: Alfred has batophobias whenever he is near towering buildings or tall trees because he has such a dread of heights.

The association of Greek batos with “height” is apparently a result of a connection of this word with the second element in acrobat because acrobats are associated with the idea that they perform their arts high over ground levels.