After spending a year in college studying in Tokyo, I moved back to Los Angeles for about two years before coming back to Japan for work. Having always prided myself on my familiarity with Japanese slang (partly to distract myself from my terrible penmanship when writing kanji characters), I was surprised to find out how many new terms had sprung up in just the 22 months I’d been away.

At the same time, it turned out that a few of the vocabulary words I’d picked up while studying abroad had since passed their expiration dates and become obsolete. This wasn’t a one-time transition, either, as language is constantly evolving, and today we bring you a list of eight words that’ll at best make you sound like a senior citizen, and at worst simply won’t be understood by anyone under the age of 25.

1. rajikase

A mashup of the Japanese pronunciations of “radio” and “cassette,” rajikase is the Japanese term for a boombox. Rajikase seems like it should be pretty self-explanatory, until you remember that thanks to streaming and MP3s, many people have never listened to the radio or used a cassette tape.

2. kasetto teepu

Likewise, if someone doesn’t have any experience with a rajikase, they’re not going to be familiar with the kasetto teepu/cassette tapes that go in them.

3. maki modosu

Literally meaning “wind it back,” this is the Japanese word for “rewind.” But how are you supposed to wind up a YouTube clip, wonder the young Japanese for whom makimodosu has never had a concrete meaning.

4. pokeberu

While pokeberu might sound like a cheap knockoff version of Pokémon it’s actually a combination of “pocket” and “bell,” or as we call it in English, a pager. Once an essential piece of gear for powerful executives, talented surgeons, and socially active teens, Japanese youths no longer need a word for pokeberu, since they’ve been superseded by smartphones. Honestly, in today’s world, trying to communicate by pager is about as convenient as sending a carrier pigeon.

5. furoppi

Deciphering this one requires swapping the “r” for an “l,” since the latter letter doesn’t exist in Japanese, giving us a “floppy,” as in a floppy disk. Again, why bother learning and remembering how to reference the relative stiffness of a computer disk when most people don’t even have the need to use physical media anymore?

6. Sufami

The full name would be Super Family Computer, which under Japanese pronunciation conventions would become suupaa famirii konnpyuuta, weighing in at a whopping 13 syllables. That got shortened down to Super Famicom for the official release of Nintendo’s much loved (and occasionally sunburned) 16-bit video game system. But with so many great games to play, enthusiasts had no time to waste saying Super Famicom, and so they pared it down once again to just Sufami.

Nintendo has released four consoles since the Sufami though, and not only do many kids today not know the truncated nickname, they don’t even see the need to shorten the already satisfactorily succinct Wii U.

7. Asshi-kun

Ashi means feet or legs, and kun is an informal title put after names, basically a more familiar version or san. Since you could translate Asshi-kun as Mr. Legs, you might think it’s a clever way of referring to a guy who’s got shapely calves, but the truth is far less complimentary.

Asshi-kun is an old-school title women bestow upon a guy they don’t really have any romantic feelings for, but are stringing along because he has a car and can drive her places. The term came into vogue during Japan’s economic boom of the 1980s, but the tougher business conditions and a general lack of interest in driving among young Japanese these days means they’re fewer guys with the means or drive to become Asshi-kun these days.

Accompanying Asshi-kun on its march towards obscurity are the phrases are Koodo-kun/Mr. Cord, who would do a girl’s technological troubleshooting for her, and Teepu-kun/Mr. Tape, who would hook her up with copies of VHS tapes and CDs. It’s a sign of women’s progress that today so many not only feel comfortable setting up their own computers, but also in pirating their own music and movies.

8. cho beri ba/cho beri gu

These companion phrases both share cho/super and beri/very, but what do ba and gu mean?

The first is an abbreviated version of “bad,” and the second is a stand-in for “good.” In other words, these are the Japanese ways of saying “super very bad” and “super very good.”

Super very redundant!

No, this isn’t a case of something that sounds more eloquent in Japanese than in English, as both phrases sound pretty silly to most Japanese listeners too. Their brief period of general acceptance is now completely over, and while you might still be able to find someone under the age of 30 who knows what cho beri gu means, saying it will probably get you the same reaction as the word “tubular” in English.

Sources: Himasoku, Ameba News