In English, both kado and sumi can be translated as “corner.”
However, in Japanese, these two words describe very different kinds of spaces.
Both come from the same Chinese character 角 (kaku), but the direction they express is completely opposite.
角(かど) kado : An Outer Corner That Sticks Out
Kado refers to something that sticks out toward the outside.
It describes the outer edge or the part that projects outward, such as the corner of a street, a building, or a piece of furniture.
Examples:
・道(みち)の角(かど)を右(みぎ)に曲(ま)がります。
Turn right at the corner of the street.
・テーブルの角(かど)に足(あし)をぶつけました。
I hit my leg on the corner of the table.
You can imagine kado as something pointed or sticking out.
It carries an energetic, outward-facing image—something that draws attention or causes movement toward the outside.
隅(すみ) sumi : An Inner Corner That Sinks In
Sumi refers to the inner edge or the part that sinks in.
It is used for the inside corners of rooms, boxes, or containers—places that feel closed or inward.
Examples:
・ゴミが部屋(へや)の隅(すみ)にあります。
There is some dust in the corner of the room.
・公園(こうえん)の隅(すみ)に小(ちい)さい花(はな)が咲(さ)いています。
A small flower is blooming in the corner of the park.
Because sumi refers to something that lies inward, it gives a calm and quiet impression.
It often evokes a sense of stillness or a place where someone feels safe and at rest.
Figurative and Abstract Uses
Both kado and sumi can describe not only physical space but also human emotions and relationships.
These figurative uses reflect the Japanese tendency to connect physical direction with inner feelings.
1) 角(かど) kado : sharp or harsh attitude
Kado can describe someone’s personality or words when they feel “sharp” or “pointed.”
It represents an attitude that pushes outward or feels confrontational.
Examples:
・そんな言(い)い方(かた)をすると角(かど)が立(た)ちますよ。
If you say it like that, it will sound harsh.
・最近(さいきん)はだいぶ丸(まる)くなりましたね。
You’ve become much gentler lately.
Here, “becoming round” (maruku naru) means that one’s kado (sharp edges) have disappeared.
In other words, a person who used to be blunt or strong-minded has become softer and more tolerant.
2) 隅(すみ) sumi : emotional depth or quiet memory
Sumi often appears in expressions about the heart or memory.
It represents small, hidden feelings that remain quietly inside.
Examples:
・心(こころ)の隅(すみ)で、まだ気(き)になっています。
I still care about it in the corner of my heart.
・記憶(きおく)の隅(すみ)に残(のこ)っています。
It remains faintly in my memory.
So, kado expresses an outward, pointed movement, while sumi shows something inward and still.
This contrast also reflects two ways of feeling and thinking in Japanese culture.
Related Expressions and Cultural Notes
・角部屋(かどべや): a room located at the corner of a building, usually with two windows.
・隅々(すみずみ)まで: means “every corner” or “throughout.”
・角(つの): the same character also means “horn” of an animal—something that sticks outward.
・角(かど)が立(た)つ: literally “a corner stands up,” meaning “a relationship becomes tense or harsh.”
・丸(まる)くなる: literally “to become round,” meaning “to become gentler or more easygoing.”
Summary
Use kado (角) for outer corners that stick out.
Use sumi (隅) for inner corners that sink in.
Kado suggests movement, energy, and outward direction.
Sumi suggests calmness, silence, and inward feeling.
These two words are more than just “corners.”
They reveal how Japanese people perceive space, emotion, and even human relationships through subtle differences in direction and feeling.