13. The "Upside-Down Box" Radical: 冂

The upside-down box radical 冂 looks quite familiar, as if it must appear in hundreds of kanji. Perhaps, but it is on duty in just four from the Joyo set:

円 (4: circle; yen)

内 (364: inside, within; private, unofficial)

再 (679: again; after next)

冊 (874: counter for books; book, issue)

Photo Credit: Eve Kushner

At the Kamakura temple 円覚寺 (えんかくじ), this sign contains 円 and 内, both featuring the on-duty 冂 radical. As I'm so accustomed to seeing 円 after a number, indicating how much something costs, I like finding it in a radically (!) different context.

The sign offers a map of the grounds, as you can tell from the words in the longer column:

境内 (けいだい: (temple) grounds)

配置図 (はいちず: map)

The Skinny on the 冂 Radical

The two-stroke 冂 is quite simple, and one of my sources indicates that it has no variants. By contrast, Nelson lists three variants, all thinner versions of the same shape. Maybe he's referring to kanji such as 剛 (1270: strong) and 洞 (1661: cave), where the slimmed-down 冂 is a mere component.

Because 冂 encloses other shapes (as in 内), the radical position name is 構え (かまえ: structure). That term is a voiced suffix in the following names for our radical:

  • けいがまえ (冏構え), meaning an enclosure like the one in the non-Joyo 冏 (bright), which has the on-yomi ケイ
  • まきがまえ (冂構え), which is quite odd because the non-Joyo 冂 does not carry the まき yomi
  • どうがまえ, meaning an enclosure like that in 同 (ドウ: same)
  • えんがまえ, meaning an enclosure like that in 円

Regarding けいがまえ, the けい might also refer to the on-yomi of the non-Joyo 冂 itself. Kanjigen indicates that that's the source of the name けいがまえ, but many other dictionaries render that radical name as 冏構え.

Incidentally, the on-duty radical in 同 is 口 (30: the "mouth" radical).

English speakers refer to the 冂 radical not only as "upside-down box" but also as "display case" and "enclose."

Photo Credit: Eve Kushner

What's this—another use of 円 that has nothing to do with prices?! Indeed, 円すい (えんすい) means "cone." Using the non-Joyo 錐, you can render this word as 円錐 (circle + cone). Adding 形 (かたち: shape) yields "conical shape," which makes sense for coffee filters.

Here is the largest text on the packaging:

Conical shape for delicious coffee

珈琲 (コーヒー: coffee, where both kanji are non-Joyo)

Permeable paper filters you can use in (the brand of drip coffee maker known as) V60

用 (よう: use); 透過法 (とうかほう: permeation method)

Conical shape

Contains 40

-枚 (-まい: counter for flat object);
-入り (-いり: containing)

Look-Alike Radicals

That packaging contains two instances of 用 (use), which might seem to feature our 冂 radical. But no, the entire 用 shape is radical 101, the “using” radical. Here are other radicals that bear some resemblance to 冂:

Photo Credit: Corey Linstrom

At Mount Fuji, a sign tells us when something was rebuilt. We know that thanks to the last word:

再建 (さいけん: rebuilding)

The first six kanji indicate the date of that event:

平成 (へいせい: name of an era, 1989–2019)

三年 (さんねん: Year 3, which was 1991)

七月 (しちがつ: July)

As for 吉日, that's enigmatic:

吉日 (きちじつ: (1) lucky day; auspicious day; (2) unspecified day of the month (used to obscure the date a letter, invitation, etc. was written))

A term intended to obscure the truth?! I love it! In this case, the 吉日 tells us that the structure was rebuilt on an auspicious day, but they're not saying which one it was!