Meaning
Whether you are reading a news article or chatting with friends, the kanji 知 is inescapable. Classified as an N4 level character, it represents the fundamental concept of "knowing," "wisdom," or "intellect." Japanese children learn this character in the second grade because it forms the basis of how we describe awareness and information.
The structure of 知 offers a poetic glimpse into its meaning. On the left sits 矢 (ya), meaning "arrow," while the right side features 口 (kuchi), meaning "mouth." Why combine an arrow with a mouth? One theory suggests that true knowledge is like an arrow hitting its target: direct, swift, and accurate. Another interpretation posits that someone with knowledge can speak (mouth) truths as straight and fast as an arrow. In ancient contexts, this character often appeared in oaths where a speaker declared facts with total certainty.
With exactly 8 strokes, 知 is balanced and satisfying to write. Start with the 5-stroke arrow radical on the left, ensuring the diagonal lines have a sharp flick. Finish with the 3-stroke square mouth on the right. Keeping both halves roughly equal in height ensures your handwriting looks professional and legible.
Readings
On'yomi (音読み) — Chinese-derived readings
The On'yomi reading for 知 is チ (chi). You will encounter this reading primarily in compound words (jukugo) related to academic, formal, or technical subjects. It implies structured or intellectual knowledge.
知識 (chishiki) — knowledge / information
知能 (chinō) — intelligence / intellect
通知 (tsūchi) — notice / notification / announcement
Kun'yomi (訓読み) — Native Japanese readings
The primary Kun'yomi reading is し.る (shi-ru), used for the ubiquitous verb 知る. This verb covers both "to find out" and "to know." While English uses "know" for everything, Japanese distinguishes between the moment of discovery (shiru) and the state of having knowledge (shitte iru).
知る (shiru) — to know / to find out
知らせる (shiraseru) — to inform / to notify (the causative form)
知り合い (shiriai) — acquaintance / someone you know
Common Words & Compounds
The versatility of 知 is best seen in how it shifts between casual and formal contexts. Here are the most essential compounds categorized by usage:
Intellectual & Educational Terms
知識 (chishiki) — knowledge. Refers to facts gained through study, such as senmon chishiki (specialized knowledge).
知恵 (chie) — wisdom. Unlike data-driven knowledge, chie is the practical savvy used to navigate life's challenges.
知的 (chiteki) — intellectual. Often used in phrases like chiteki koukoushin (intellectual curiosity).
Social & Interpersonal Terms
知り合い (shiriai) — acquaintance. Someone you recognize and talk to, but who isn't quite a tomodachi (friend).
知人 (chijin) — acquaintance (formal). You will see this in business emails or formal introductions.
承知 (shōchi) — consent / acknowledgement. Shōchi itashimashita is the standard humble way to say "I've understood and accepted your request."
Communication & Awareness
通知 (tsūchi) — notice. This applies to everything from phone push notifications to official tax notices.
未知 (michi) — unknown. Literally "not yet known," describing unexplored territory or undiscovered scientific facts.
無知 (muchi) — ignorance. A literal lack of knowledge (mu = none).
Example Sentences
Observe how the reading shifts from the native shi in verbs to the Chinese-derived chi in formal compounds.
彼の名前を知っていますか？
kare no namae wo shitte imasu ka?
Do you know his name?
明の予定を知らせてください。
ashita no yotei wo shirasete kudasai.
Please let me know tomorrow's schedule.
あの人は日本歴史の知識がとても豊富です。
ano hito wa nihon rekishi no chishiki ga totemo hōfu desu.
That person has a wealth of knowledge about Japanese history.
その件についてはすでに承知しております。
sono ken ni tsuite wa sude ni shōchi shite orimasu.
I am already aware of that matter (humble expression).
スマホにアプリの通知が届きました。
sumaho ni apuri no tsūchi ga todokimashita.
I received an app notification on my smartphone.
未知の世界を探検したいです。
michi no sekai wo tanken shitai desu.
I want to explore the unknown world.
困ったときは、お祖いちゃんの知恵を借ります。
komatta toki wa, ojiichan no chie wo karimasu.
When I'm in trouble, I rely on my grandfather's wisdom.
誰もその理由を知りません。
dare mo sono riyū wo shirimasen.
Nobody knows the reason for that.
Related Kanji
- 走 — Run, Move fast (Kanji N4)
- 思 — To Think, Feel, Imagine (Kanji N4)
- 死 — Death, Die (Kanji N4)
- 題 — Topic, Subject, Problem (Kanji N4)
- 業 — Business, Vocation, Arts, Karma (Kanji N4)
- 開 — Open, Unfold, Begin (Kanji N4)
Memory Tip
Visualize a wise person engaging in a debate. When they open their mouth (口), their words strike with the precision of an arrow (矢). Because they truly know the subject, their speech is sharp and never misses the mark. Remember: An "Arrow-Mouth" always speaks the truth!