When I was a kid 50-60 years ago, I spent a lot of time on the B&O YMCA porch next to the tracks and across from the roundhouse at Brunswick Maryland. An engine service facility and a yard out of sight either direction, one each for east and west bound. I’d spend all day watching trains go by, engines being serviced, etc. As happened time to time back then, a hostler saw me there every day, and beckoned me over to the roundhouse, wher I got to climb onto his GP7, and I got to move it onto the turntable and then back off it on a different track. Under his eye of course.
I recall proudly announcing this was a “EMD GP7”, but he just called it a GM engine. Gee, I had thought they used the same terms we do.
So, in general, did railroaders use names like Mikado and Pacific, SD9 and NW1, or did they mostly use K4 and Q2 and DF? Or whatever. Or did they use slang I have no idea of? Or did they just call them by the numbers. “We have the 4393 today, Joe.” Or “There’s a couple of 4300’s on the ready track.”
You get the idea.