Hey Bronze21... this is going to really get me hammered in light of the rest of your posting above regarding trains but here goes anyway....
Anorak.... Well it's the sort of derogatory term used in England for someone who's just a little too "into" a particular hobby. They'd get very obsessive (often violent) about accuracy and details and would be without a girlfriend, let alone a wife! Their Mother wouldn't approve of another female having any influence over her darling son!
The origin of "Anorak" is based upon... ummm

and don't take this personally eh Bronze21..... Train enthusiasts, in particular Train Spotters. Grown men in their 40's who'd stand beside railways tracks clutching a dog-earred notepad, a tarten thermos flask of tomato soup by their feet. Wrapped up in a scarf their mum knitted for them when they were 14 and wearing a bobble hat (don't ask) white socks with trouser cuffs slightly too short and finally the anorak. A zip-up lightweight nylon jacket, usually navy blue with a red stripe somewhere on it and drawstrings. It also has a hood, sometimes detachable, which was so small it didn't quite cover your ears when put up.
These said 'men' would wait for hours, even in the rain, for that one particular illusive "Golden" train. When it arrived they'd go into throes of almost orgasmic pleasure after finally 'getting' it. They'd jot the train's number down onto their notepad and do the strange "I got it!" dance (like the way your Dad dances at wedding receptions but much, much worse). Then patiently wait another 3 hours in case another train came along such as the legendary 4.28pm from Clapham South, whose number they hadn't got yet, then walk home (they don't drive, Mother wouldn't approve) to their single bedsit room, or worse, the house they still share with their aged Mother. Where thier room would still have plastic model aircraft of Spitfires hangin from the ceiling in a dog fight with ME109s and posters of Slade and Charlie George of Arsenal on the wall.
This same derogatory term anorak could be applied to any other hardcore hobbyist such as fishermen (rod and reel type), birdwatchers or stamp collectors (though stamp collectors are rarely found outdoors, but if seen, are easily recognised by their pale complexion and thick glasses, however they still fall under the umbrella term of "Anorak") but the fabled Trainspotter got in there first. Sadly they're a dying breed now since anoraks with red stripes are no longer beng made.
Betcha wished you hadn't asked now huh?

again no offense intended to you personally Bronze21-MFP460
Anyone else from the UK want to elaborate further?....and kick a man while he's already down?
Biker
PS No offense intended to any fisherman, stamp collectors or bobble hat wearing birdwatchers.
PPS How did this thread ever end up here?