Now one rail enthusiast has broken ranks and lifted the lid on the peculiar slang that populates platforms up and down the country.
Rod Warrington, a member of the Friends of the Settle-Carlisle Line, has written about the sub-culture that obsesses fellow enthusiasts.
His glossary for the trainspotter is included in this month's issue of the campaign group's magazine.
Here is a pantheon where "gricing" (the trainspotters' term for their noble art) is home to "festoons" - older gricers encumbered with cameras, tape recorders and other gadgets.
"The young number-takers take the mickey out of the people with the tape recorders," explained Peter Shaw of the Friends of the Settle-Carlisle Line.
The "Festoons" in turn ridicule the obsessive train number collectors ("bashers"). "Bashers" are further sub- divided by their devotion to different locomotives, trains or routes and carry the monikers of "steam-bashers", "wagon-bashers" and "line-bashers".
Signals become "pegs" or "sticks" and engines can be "doughnuts" (see- through engine), "choppers" (with a sound like a helicopter) or "nodding donkeys" (a bumpy ride).
Mr Warrington, 54, from Chester, said that the trainspotting oeuvre was taken very seriously by enthusiasts. "Some swear if you walk in front of their cameras. Others race trains by car. They are just maniacs."
Mr Warrington's own vice is the Settle-Carlisle line. He said: "I diagnosed my problem as Settleandcarlisleitis, apparently incurable and regarded by unfeeling wives and partners not so much as an infectious bug but as a psychiatric compulsive disorder."
He added there was an increasing amount of jargon that even he had never heard of. "I was told that `gricing' was now the correct term for what we would be doing. Apparently `trainspotting' had become passe," he said.
Betty Kirkpatrick, editor of Roget's Thesaurus, said "gricer" had already made it to the dictionaries to indicate a railway enthusiast.
"It is the nature of all groups to have their own jargon," said Ms Kirkpatrick. "It's almost like being in a secret society and having passwords, words of acceptance. It's a vocabulary designed to exclude as much as it includes."