LESSON NOTES · レッスンノート

N5Lesson notes · Oct 4, 2026

黒くろい (くろい) means black in Japanese: 真っ黒まっくろ, 腹黒はらぐろい, 黒くろ歴史れきし

黒くろい (くろい) is the adjective "black" in Japanese, and 黒くろ (くろ) is the noun. Pitch black is 真っ黒まっくろ (まっくろ). Black also carries meaning: 黒字くろじ (くろじ) is a profit, 腹黒はらぐろい (はらぐろい), "black-bellied", means scheming, and 黒くろ歴史れきし (くろれきし), "black history", is slang for an embarrassing past you would rather forget.

Black in Japanese is a color of formality, mystery and, sometimes, guilt. You wear it to funerals and job interviews, it marks a suspect as "guilty" in police slang, and online it labels your cringeworthy teenage poems. The katakana ブラック is used too, for coffee and for exploitative companies. This post covers all the main uses.

How do you say "black" in Japanese?

What is the difference between 黒くろ and 黒くろい?

黒くろ (くろ) is the noun "black", and 黒くろい (くろい) is the い-adjective.

黒くろい猫ねこがいる。 — There's a black cat. (casual) 黒くろが似合にあうね。 — Black suits you. (casual)

For the grammar of color words, see Japanese colors.

What does 真っ黒まっくろ mean?

真っ黒まっくろ (まっくろ) means pitch black or completely black. It is also used for a deep tan or burnt food.

日焼ひやけで真っ黒まっくろになった。 — I got really tanned. (casual) トーストが真っ黒まっくろだ。 — The toast is burnt black. (casual)

Do not confuse it with 真っ暗まっくら (まっくら), pitch dark, and darkness in Japanese separates 暗くらい, little light, from 黒くろい, a color.

What is ブラック?

ブラック is used for black coffee and in ブラック企業きぎょう, an exploitative "black company". See black company in Japanese.

コーヒーはブラックで。 — Black coffee, please. (casual, ordering)

What does black mean beyond color?

What does 黒字くろじ mean?

黒字くろじ (くろじ), "black letters", is a profit. The opposite is 赤字あかじ (あかじ), a loss.

今年ことしは黒字くろじになった。 — We made a profit this year. (casual)

What does 腹黒はらぐろい mean?

腹黒はらぐろい (はらぐろい), "black-bellied", means scheming or two-faced: nice on the outside, calculating inside.

あの人ひと、優やさしそうだけど腹黒はらぐろい。 — He seems nice, but he's scheming. (casual)

What does 白黒しろくろつける mean?

白黒しろくろつける (しろくろつける), "to settle white and black", means to settle who is right, or to get a clear answer.

今日きょうこそ白黒しろくろつけよう。 — Let's settle this once and for all today. (casual)

Word Reading Meaning
黒くろ くろ black (noun)
黒くろい くろい black (adjective)
真っ黒まっくろ まっくろ pitch black
黒字くろじ くろじ profit
腹黒はらぐろい はらぐろい scheming
白黒しろくろつける しろくろつける to settle it
黒くろ歴史れきし くろれきし embarrassing past
黒髪くろかみ くろかみ black hair

Beyond the basics

What is 黒くろ歴史れきし?

黒くろ歴史れきし (くろれきし), "black history", is slang for something embarrassing from your past: an old blog, a cringey phase, a bad haircut.

中学ちゅうがくの時ときの写真しゃしんは黒くろ歴史れきしだ。 — My middle school photos are my embarrassing past. (casual)

What does 黒くろ mean in police slang?

In crime dramas, 黒くろ means "guilty" and 白しろ means "innocent". 限かぎりなく黒くろに近ちかい is "almost certainly guilty".

あいつは黒くろだ。 — He's guilty. (casual, drama style)

When do people wear black?

Black is the color of funerals in Japan: 喪服もふく (もふく) is mourning clothes. Black suits are also standard for job hunting, as part of the リクルートスーツ.

お葬式そうしきには黒くろい服ふくを着きる。 — You wear black clothes to a funeral. (casual)

What do 黒幕くろまく and 黒帯くろおび mean?

黒幕くろまく (くろまく), "black curtain", is the mastermind pulling strings behind the scenes, a favorite twist in mystery anime. 黒帯くろおび (くろおび) is a black belt in martial arts.

実じつは先生せんせいが黒幕くろまくだった。 — It turned out the teacher was the mastermind. (casual, a plot twist) 空手からての黒帯くろおびを持もっている。 — I have a black belt in karate. (casual)

Common mistakes

  • Saying 黒くろいが好すき. The noun is 黒くろ: 黒くろが好すき.
  • Reading 真っ黒まっくろ as まっくろい. As a noun it is まっくろ; 真っ黒まっくろな or 真っ黒まっくろい both work as modifiers.
  • Mixing up 黒字くろじ and 赤字あかじ. 黒字くろじ is profit.
  • Using 腹黒はらぐろい as a compliment. It is critical.
  • Thinking you must say ブラックコーヒー. That word is fine, but when ordering, コーヒーはブラックで sounds natural.

Practice

Try each answer before opening it. Questions 5 and 6 are a pair: profit versus loss.

1. Say "There's a black cat."

Show answer

黒くろい猫ねこがいる。 — 黒くろい.

2. Tell a friend black suits them.

Show answer

黒くろが似合にあうね。 — the noun 黒くろ.

3. Say "I got really tanned."

Show answer

日焼ひやけで真っ黒まっくろになった。 — 真っ黒まっくろ.

4. Order your coffee black.

Show answer

コーヒーはブラックで。 — ブラック.

5. Say "We made a profit this year."

Show answer

今年ことしは黒字くろじになった。 — 黒字くろじ.

6. Say "We made a loss this year."

Show answer

今年ことしは赤字あかじになった。 — 赤字あかじ. This is the pair to question 5.

7. Say "He seems nice, but he's scheming."

Show answer

あの人ひと、優やさしそうだけど腹黒はらぐろい。 — 腹黒はらぐろい.

8. Say "Let's settle this once and for all today."

Show answer

今日きょうこそ白黒しろくろつけよう。 — 白黒しろくろつける.

9. Say "My middle school photos are my embarrassing past."

Show answer

中学ちゅうがくの時ときの写真しゃしんは黒くろ歴史れきしだ。 — 黒くろ歴史れきし.

10. Fix: 黒くろいが好すきです。

Show answer

黒くろが好すきです。 — use the noun.

黒くろ歴史れきし is a word people laugh at, so confess one embarrassing memory in Japanese in a trial lesson and then describe a 腹黒はらぐろい anime villain.

FAQ

How do you say "black" in Japanese? 黒くろ (くろ), or 黒くろい as an adjective.

What does 真っ黒まっくろ mean? Pitch black.

What does 黒字くろじ mean? A profit.

What does 腹黒はらぐろい mean? Scheming or two-faced.

What is 黒くろ歴史れきし? An embarrassing past you want to forget.

How do you order black coffee? コーヒーはブラックで.

Vocabulary from this article

Tap the block to select all of it, then copy. In Anki: File → Import, note type Basic, separator Tab — the first column becomes the front, the second the back.

黒	くろ — black
黒い	くろい — black (adjective)
真っ黒	まっくろ — pitch black
黒字	くろじ — profit
赤字	あかじ — loss
腹黒い	はらぐろい — scheming
白黒つける	しろくろつける — to settle it
黒歴史	くろれきし — embarrassing past
日焼け	ひやけ — tan, sunburn
喪服	もふく — mourning clothes
黒幕	くろまく — mastermind
黒帯	くろおび — black belt

I'm Yuuki, a Japanese teacher based in Tokyo. I've taught on italki as a Top 1% teacher and watched over 1,500 anime. 黒くろ歴史れきし is the slang word learners laugh at most, and 腹黒はらぐろい is the one they need to describe half the villains in anime. For practice with feedback, Book a trial lesson · $13, or try the Japanese practice exercises first.

Sources: the author's own lessons and standard reference dictionaries.

More drills like the ones above, plus a timed JLPT-style mock test: Practice · N5 · Read something at this level: JLPT N5 stories with audio

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