In 2025, the Oxford English Dictionary added 11 Japanese words that cover a wonderfully chaotic range, from folklore monsters to snack foods, not to mention the greatest invention of all time: the modern miracle of the heated toilet seat.
Although The Japan Times recently posted a similar list, theirs is paywalled and includes “brush pen,” which wasn’t added chiefly with reference to Japanese culture. That list also omits “waifu,” (yes, that waifu) which was added in March. Each entry contains the OED definition, along with a Japanese example sentence + English translation, as well as some additional context or notes when applicable.
Here are the entries! Which ones have you heard of before?
1. Ekiden（駅伝・えきでん）
- OED Entry: “A long-distance relay race, first held in Japan in 1917, in which each member of a team of runners covers a different distance, and a sash is passed from one member to the next. Frequently as a modifier, as in ekiden marathon, ekiden race, ekiden relay, etc.”
JP) 来年も箱根駅伝は青山学院大学が優勝するでしょう。
ENG) Aoyama Gakuin University will probably win the Hakone ekiden next year, too.
Ekiden is Japan’s signature long-distance relay format, built around “stations” (eki, 駅) and “relay transmission” (den, 伝), a nod to the old station-to-station courier system that inspired the modern race style. Runners pass a tasuki (襷), a sash worn across the chest, and that handoff is essentially the emotional core of the sport, with strict rules and time cutoffs that can cause dramatic changes and upsets throughout the race. The most famous event is the Hakone Ekiden (箱根駅伝), a huge New Year fixture run over two days (January 2-3) on a route from Tokyo to Hakone and back, totaling 217 km in 10 sections — five runners outbound, five inbound — and featuring university teams from the Kanto region.
2. Love hotel（ラブホテル）
- OED Entry: “A short-stay hotel where rooms can be rented for discreet sexual or romantic encounters (originally and chiefly with reference to such hotels in Japan).”
JP) 渋谷の路地を一本入ると、ラブホテルだらけだ。
ENG) If you turn off into one of Shibuya’s side streets, it’s full of love hotels.
Love hotels are a purpose-built answer to a practical problem: dense cities, thin walls, multigenerational homes, and couples who would like a door that locks and a checkout process that does not involve making eye contact with anyone. Need anything else be said?
Note: can be abbreviated to ラブホ
3. Mottainai（もったいない）
- OED Entry: “Expressing regret over or disapproval of something which is considered to be irreverent or wasteful.”
JP) まだ使えるのに捨てるなんて、もったいない。
ENG) Throwing it away even though it still works is such a waste.
JP) その才能、趣味だけで終わらせるのはもったいない。
ENG) It’d be a shame to keep that kind of talent as “just a hobby.”
“What a waste” covers the surface meaning, but mottainai often carries a moral or emotional note as well, such as respect for resources, gratitude, and the feeling that the object (or opportunity) deserved better.
4. Naginata（薙刀・なぎなた）
- OED Entry: “A traditional Japanese polearm consisting of a long wooden or metal shaft with a curved single-edged blade. In later use: a polearm of similar design made of wood, bamboo, or leather, used in a martial art now practised chiefly by women and girls in modern Japan. Also: this martial art.”
JP) 彼女は薙刀を持つと人が変わる。
ENG) The moment she holds a naginata, it’s like she turns into someone else.
Historically, the naginata shows up in warfare, temple defense, and martial training. In popular memory, it is often associated with women of the warrior class and with disciplines taught for household defense, though the broader history is more complex than a single image. In modern Japan, naginata also refers to a practiced martial art (competitive and non-competitive forms), so the word can point to (pun totally intended) both the weapon and the sport.
5. PechaKucha（ペチャクチャ）
- OED Entry: “A fast-paced presentation format originating in Japan, in which a speaker may show only twenty slides, each displayed for only twenty seconds, resulting in a concise, engaging talk with visually impactful images. Also: a presentation in this format. Frequently as a modifier.”
JP) 今日はペチャクチャ形式で発表するから、時間厳守でいこう。
ENG) Today we’re presenting in PechaKucha format, so let’s stick to the time limit.
The name comes from Japanese onomatopoeia for chatter (ぺちゃくちゃ). Apparently, the presentation format was created in Tokyo in 2003 by architects Astrid Klein and Mark Dytham, originally to keep design talks brisk.
6. Senbei（煎餅・せんべい）
- OED Entry: “A savoury or (sometimes) sweet Japanese rice cracker of various sizes, shapes, and flavours, usually eaten as a snack and served with green tea.”
JP) おせんべいの時にはやっぱりお茶だね。
ENG) Senbei just hits better with tea, doesn’t it?
I mean, what’s not to love about senbei? You’ve got light and crisp ones, or the thick and crunchy kind. They can be sweet, salty, glazed in soy sauce, seaweed-wrapped, or spicy. They sit beautifully alongside crackers and chips (crisps, if you’re feeling British), but the rice base and savory staples like shōyu and nori make them taste unmistakably Japanese.
7. Senpai（先輩・せんぱい）
- OED Entry: “In Japan and Japanese contexts: a member of a group or organization considered senior on account of age or experience, who can give guidance or assistance to a junior member. Also as a respectful title or form of address. In extended use (chiefly among fans of manga and anime): a person one admires and whose attention one craves.”
JP) 先輩、ちょっと相談してもいいですか。
ENG) Senpai, can I ask you for some advice?
English can translate senpai as “senior,” “upperclassman,” or “mentor,” but the Japanese relationship is typically more structured. The senpai–kōhai (後輩) dynamic often includes informal responsibilities, like teaching newcomers, social introduction, and sometimes a subtle expectation of loyalty and deference in return. Then the internet got involved (“notice me, senpai”).
8. Waifu（俺の嫁・おれのよめ）
- OED Entry: “A fictional female character from a video game, anime, manga, etc., whom a person (typically a man) regards as an actual or ideal romantic partner.”
JP) 俺の嫁はエアリスだ。
ENG) Aerith is my waifu.
Instead of ワイフ, Japanese fans more often say 俺の嫁 (おれのよめ), hence the translation. For an actual spouse, normal Japanese is 妻 (つま) or 奥さん (おくさん), not ワイフ.
9. Washlet（ウォシュレット）
- OED Entry: “A proprietary name for: a toilet seat with a nozzle that sprays water to wash one’s genital and anal area, as well as other features such as a heated seat and a control panel or remote control for operating the toilet functions and adjusting water pressure, temperature, and other settings.”
JP) このホテル、ウォシュレット付きで助かった。
ENG) This hotel has a Washlet, thank goodness.
The Washlet is closely associated with TOTO, and the product line is often traced back to an early consumer launch around 1980, after which the idea spread widely in Japan. At this point, “Washlet” has become a generic trademark (think Kleenex, Band-Aids, or Post-Its), and it also acts as cultural shorthand. If someone says, “Japanese toilets,” half the time they mean “the Washlet experience,” delivered with utmost reverence. Indeed, I’m a convert who cannot live without one now that I’ve been spoiled for so long.
10. White Day（ホワイトデー）
- OED Entry: “Originally in Japan, later also in other East and Southeast Asian countries: a holiday celebrated on 14 March, on which men reciprocate the presents they receive from women on Valentine’s Day by giving them chocolate or other gifts, esp. items that are white in colour.”
JP) ホワイトデーのお返しを買いに行った。
ENG) I went to buy a return gift for White Day.
As the definition notes, in Japan, Valentine’s Day customs often involve women giving gifts (commonly chocolate), and White Day developed as the reciprocal gifting date a month later. Accounts of its commercial origin typically point to the late 1970s and confectionery-industry promotion, after which it became a stable part of the calendar.
11. Yōkai（妖怪・ようかい）
- OED Entry: “Any of various spirits or supernatural beings in Japanese mythology and folklore and in modern Japanese fiction, esp. anime and manga.”
JP) 妖怪の話は怖いけど、つい読んでしまう。
ENG) Yōkai stories are scary, but I can’t help reading them.
Yōkai is a pretty broad category: some are basically monsters, some are tricksters, some are “explaining the unexplainable” in story form. Modern pop culture keeps yōkai alive, sometimes by naming them outright and sometimes by borrowing their “rules” and aesthetics. Series like GeGeGe no Kitarō make yōkai the main cast, treating folklore creatures as recurring characters with personalities and grudges, while games do the same job in different tones: Yo-kai Watch turns them into collectible troublemakers behind everyday mishaps, and darker action titles like Nioh use yōkai as genuinely threatening supernatural enemies. Even films that are not framed as a folklore encyclopedia per se can feel yōkai-adjacent in how they build a parallel world with its own etiquette and dangers, like Spirited Away. A couple of popular ones you may have heard of before are the kappa (河童), a sometimes-cute-sometimes-dangerous creature associated with rivers and lakes, and tengu (天狗), a mountain dweller often depicted with a long nose and tied to martial prowess and spiritual power.
If you’d like, you can browse the OED website to see the rest of their additions for 2025: https://www.oed.com/information/updates
