The most common and most likely answer to this crossword clue is the 12 letter word TRAINSPOTTER
I've seen this crossword clue in Financial Times
T
R
A
I
N
S
P
O
T
T
E
R
More clues leading to the result TRAINSPOTTER
- Series proceed at too leisurely a pace for nerdy enthusiast?
- Platform regular practises with craftsman
- Studies dramatist in anorak
- What Snape does, being on Platform 9 3/4?
- Welsh character coaches snooker player
- Railway buff that’s wizard on coaches
- Recorder of numbers gives magical lessons?
- Following disorganised protest in anorak
- Nerdy type teaches Harry new tricks maybe
- What a ceramics teacher does for an obsessive collector
Buddy explains!

The straight part
We know that "anorak" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case anorak = trainspotter.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TRAINSPOTTER mean?
TRAINSPOTTER noun- A person whose hobby is train spotting.
- (by extension) An obsessive follower of any minority interest or hobby.