...I wondered about that...

I thought the prefix just meant "siderods," the word between the combining form "O" & phobia "drom" threw me off, thanks for the info.
I developed this phobia as a young child from the noise of freight cars on stick rail, and an ALCo H660 the Tennessee Central Railroad ran through Cookeville, TN.
It hung with me until about 12-years old, I had forgot it until I walked down through a citrus grove to watch the Ft. Meade Turn work Eaton Park on the Ft. Myers Subdivision of the Seaboard Coast Line.
I was very much interested in the GP7's that worked that turn, however the assembled train was something I had to get over.
I sat on a bridge support at the end of a bridge about five feet from the main one day, a southbound hot-shot hit the other side of the bridge and a SD45 "hunted" the rails across the bridge right at me...after that I never had another problem.
It does bother me that people get too close for pictures of an approaching train, even though they are just using a tripod.
Shooting videos or picture through a grade crossing also bothers me, if a car pulled in front of the train it would wipe out the camera.