電車オタクって英語でなんて言うの？

In the UK train spotters are common. They stand or wait at certain points along a trains route and wait for it to pass to take photos or just to see the train with their own eyes. The trains in question are not usually modern trains in the UK, but older steam engines from the mid to early 20th century. A common place to watch the steam engine from is a railway bridge. The 'Flying Scotsman' is probably one of the most famous trains in the world for 'Train Spotters'. To 'spot' something means to have seen it. 'Buff' or 'enthusiast' are two words that means very similar things. They mean that someone is really keen, interested and into something. Another example may be "He is a movie buff."

"Train Addict" In addition to the words, the others have posted here. Train addict is a very common way in the U.S. to call someone who is a train enthusiast. The key word here is addict. Even though this word carries a negative stigma is not a bad word. Using the word addict in this type of sentence is just letting people know that the person is an enthusiast or really enjoys something, for example, a car addict loves everything about cars, fashion addict loves everything about fashion and so on.

Someone who is a very interested in a particular topic or subject is known as an 'enthusiast' or 'buff' so if someone is very interested in trains then we would call them a 'train enthusiast' or 'train buff' In the UK we use the term 'train spotter' for someone that goes and looks for/takes photos of different trains this is very common as well

the term 'train spotter' is a term given usually in England and Ireland for someone who is enthusiastic about train (train enthusiast) 'spotter' is taken from the word 'Spot' which describes to find or see a particular thing "I am enthusiastic about trains, I am a train enthusiast"

If you are a fanatic it means that you are obsessed with something. Calling someone a train fanatic means that they absolutely love trains. An enthusiast is a person who is very interested in a particular thing or activity. A train spotter is someone that looks at trains passing and typically takes photographs. All of these expressions are used to describe someone that is very interested in trains.

You can use the English word enthusiast and it will work just fine. You can say some one is a wine enthusiast or a running enthusiast. This denotes a high level of interest. If on the other hand, all they talk about is trains, you can describe them as a "train fanatic". You can also say they are "fanatical". In this context, fanatic is a good thing and it is said in a friendly manner.

Someone who is very interested in something is known as an enthusiast. Therefore someone who is particularly interested in trains will be known as a train enthusiast. "My father loves trains so much, he's a train enthusiast!"

You want to know what you call someone who is very enthusiastic/interested in trains? In Japanese you say "densha otaku" which means something like "train enthusiast". In the UK, someone who watches trains is called a 'trainspotter'. An 'anorak' is UK slang which refers to someone who has a very strong or obsessive interest in niche subjects - not necessarily trains - could be something else - such as birdwatching for example.