October 22, 2008

รถไฟฟ้า: sky train or electric train?

The phrase รถไฟฟ้า is an interesting linguistic specimen. Prior to the opening of Bangkok's first subway line, รถไฟฟ้า referred exclusively to the BTS (Bangkok Mass Transit System), commonly referred to in English as the Skytrain.

If you dissect รถไฟฟ้า, you can separate it as รถไฟ rot fai (train) + ฟ้า faa (sky). Skytrain, right? Maybe not.

Another way to divide up the phrase is รถ rot (vehicle) + ไฟฟ้า fai faa (electricity). Electric vehicle.

The common name for the subway is รถไฟใต้ดิน rot fai (train) + tai din (underground). Which seems like a nice semantic pair with รถไฟฟ้า. You have the sky train and the underground train.

The official name of the subway, however, is รถไฟฟ้ามหานคร rot fai faa mahaa nakhon (abbreviated รฟม.). This leaves us only one option for interpretation: metropolitan electric train. Its official English name is the Mass Rapid Transit (abbreviated MRT).

Is it possible that รถไฟฟ้า means both "sky train" and "electric train" at once? Sure, why not. Both are logical interpretations. Sometimes you'll hear the Skytrain called รถไฟลอยฟ้า rot fai loi faa (elevated/floating train), to be more specific. Before there was no need to distinguish. You could just say รถไฟฟ้า and be understood. As a result, it seems to me that I hear more and more Thais now just call it BTS บีทีเอส.

Technically speaking, an electric train should be รถไฟ rot fai + ไฟฟ้า fai faa, but I think รถไฟไฟฟ้า rot fai fai faa is understandably awkward.

If you ask native Thais whether รถไฟฟ้า means "electric train" or "sky train", you'll likely get different answers depending on who you ask. With the opening of the subway, I'd guess more people accept it to mean "electric train".

Back in January 2002, this question was posted on the BTS discussion board:
...พอดีมีคำถามที่สงสัยมาตั้งแต่รถไฟฟ้าเพิ่งจะก่อสร้างแล้วว่า "รถไฟฟ้า" หมายความว่า "รถไฟ" ที่วิ่งแบบลอยฟ้า หรือว่า รถที่วิ่งได้ด้วย "ไฟฟ้า" ครับ เอ... หรือหมายถึงทั้งสองอย่าง แต่จะเรียกรถไฟฟ้าลอยฟ้า หรือ รถไฟไฟฟ้า มันจะเรียกยากและยาวไป เลยเหลือแค่ "รถไฟฟ้า"

"I've been wondering this since construction on the skytrain had barely started--does rot fai faa mean a train that's elevated or a vehicle that runs by electricity? Or does it mean both, but calling it rot fai faa loi faa (elevated electric vehicle) or rot fai fai faa (electric train) is too difficult and too long, so it's shortened to rot fai faa?
See, it's not just me who thinks about this stuff.


  1. it's not just you who thinks about this stuff. I was used to thinking of the skytrain when I heard รถไฟฟ้า, but at Chiang Mai University, they have elongated electric golf carts for on-campus transportation. They call them รถไฟฟ้า too. I guess it translates into "electric vehicles," but I kept on thinking about skytrains...

  2. Good point. What will electric cars come to be called, when and if they ever go mainstream?

    I imagine it will be รถยนตร์ไฟฟ้า formally, but I wonder if it will get shortened to รถไฟฟ้า in common usage, or will that be too confusing? Not in Chiang Mai, apparently, but it could easily be confusing to Bangkokites (Bangkokians?).

    That's assuming that electric cars ever go mainstream.

  3. I also found it amusing that the first response to the question on the BTS site was:


    "You have too much free time on your hands." :P

  4. And it will become even more confusing when they finally build the other half of the blue ring of the subway - which will be elevated - or the BTS extension from National Stadium to Phranok, which I read will be underground as it would pass near Wat Phra Kaeo... But given the speed they implement the Taksin extension it will still be at least a decade we will see any of those.

  5. I've read about the various extensions, drooling with anticipation, but this is the first time I've ever heard that the subway will sometimes go above ground, and the skytrain will sometimes go underground. That's so Thailand.

    I predict that if/when this happens, this will just further push BTS/บีทีเอส into becoming the most common term for what we now call the skytrain, and MRT for the subway (though I have yet to hear any Thai call it by its Thai initials, รฟม.)

    Either that or it will become common to just refer to the specific line by color, as is the case in many big cities.

    Really, though, we just need one to buy out the other and integrate them better. Right now it's a big pain to switch from one to the other. I always figure for a ten minute walk/wait between the two. Inefficient.

  6. Thai Wikipedia also mentioned this word as well at http://th.wikipedia.org/wiki/รถไฟฟ้า

    So the electric car is usally called "รถพลังงานไฟฟ้า" - electric power car instead.

  7. Interesting thoughts (and I had also wondered about this before!) A final note, following up on the last comment: the Thai Wikipedia article about the Skytrain is actually - somewhat cumbersomely - entitled รถไฟฟ้าเฉลิมพระเกียรติ 6 รอบพระชนมพรรษา ("Electrical Train Celebrating His Majesty's 6th Cycle Birthday", or something similar) - the official name of the system.

  8. Thanks for the post.

    I've been studying Thai for two months but I'm also an Electrical Engineer. The moment I found the word for electricity I was confused how to interpret rot fai faa.

    Electric trains were around before the sky train, surely there must be a Thai word documented for electric train?