Railfan vs. Ferroequinologist — What's the Difference?

A railfan, rail buff or train buff (American English), railway enthusiast or railway buff (Australian/British English), trainspotter or ferroequinologist is a person interested, recreationally, in rail transport.Railfans of many ages can be found worldwide. They often combine their interest with other hobbies, especially photography and videography, radio scanning, railway modelling, studying railroad history and participating in railway station and rolling stock preservation efforts.

A student of ferroequinology; a person who studies trains as a hobby.

(US) A railway enthusiast.