"Bronte" means thunder. "Phobos" means fear. Brontophobia is the fear of thunder. Every human is afraid of two things - loud noise and falling. Thunder is a very loud noise. Brontophobes are more than just afraid, however. A phobia is an illness where the fear has reached the point of causing severe changes in the person's life. A brontophobe will go to great lengths to avoid thunder.
A brontophobe is someone who has a fear of thunder.