Meaning
The kanji 厚 (あつ・い, コウ) is a versatile character with core meanings centered on 'thickness,' 'depth,' 'cordiality,' and 'generosity.' Primarily, it describes the physical dimension of something being 'thick' or 'bulky.' Think of a thick book or a heavy blanket. This tangible meaning is commonly used to describe everyday objects.
Beyond its literal sense, 厚 metaphorically describes abstract qualities. It can convey the 'depth' or 'richness' of concepts, knowledge, or feelings, suggesting a substantial and profound quality. For instance, someone might possess a 'deep' understanding of a subject. It also beautifully captures 'cordiality,' 'kindness,' or 'generosity' in human interactions. Just as a thick blanket provides comfort and warmth, generous kindness offers support and solace.
Looking at its origins, 厚 is often interpreted as a semantic-phonetic compound. The upper part, 厂 (gake), depicts a cliff or a protective shelter. The lower component, historically 𠫝, combines 日 (sun or day) and 子 (child). This visual imagery suggests a child (子) growing strong and substantial under the protection of a cliff (厂), basking in the sun's warmth (日). This evokes ideas of solidity, density, and robust growth, naturally leading to meanings like 'thickness' and 'richness.' The sense of protection and nurturing further contributes to its metaphorical uses for 'kindness' and 'generosity.'
Consisting of 9 strokes, 厚 is taught in the 3rd grade of elementary school in Japan. This makes it a common and essential character for learners progressing through the JLPT N3 level and beyond.
Readings
On'yomi (音読み) — Chinese-derived readings
The on'yomi of 厚, pronounced コウ, stems from its historical Chinese pronunciation. You'll primarily encounter it when 厚 forms part of a compound word with other kanji. This reading often adds a more formal or abstract nuance to the compound. Familiarity with the on'yomi is vital for understanding a wide range of academic, business, and formal expressions.
コウ (KŌ): This is the single, main on'yomi for 厚. It frequently appears in terms describing physical thickness, but also extends to abstract qualities like depth of feeling, generosity, or even a lack of shame.
厚意 (kōi) — kindness, favor, good will. This term signifies a substantial or deep-seated feeling of benevolence. For example, you might use this word to express gratitude for someone's generous help.
厚紙 (kōshi) — thick paper, cardboard. Here, コウ is used in its most literal sense, describing the physical thickness of a material, distinguishing it from thinner paper.
厚顔 (kōgan) — impudence, shamelessness. Literally "thick face," this compound describes someone brazen or audacious, showing no embarrassment or shame even when expected. It's a strong negative descriptor.
厚遇 (kōgū) — warm reception, cordial treatment, hospitality. This signifies a generous and considerate way of treating guests or subordinates, often implying a high degree of respect or favor.
Kun'yomi (訓読み) — Native Japanese readings
Kun'yomi are native Japanese readings for a kanji. They are typically used when the kanji stands alone or is followed by okurigana (trailing hiragana that complete the word). For 厚, its primary kun'yomi directly expresses both physical and metaphorical thickness.
あつ-い (atsu-i): This is the predominant kun'yomi for 厚, forming an i-adjective. It's a versatile word, describing the physical thickness of flat objects (like a book, a wall, or a slice of food), the heaviness of clothing, or the warmth and cordiality of feelings and treatment.
厚い (atsui) — thick. This is the everyday adjective form. Examples include 厚い 本 (a thick book), 厚い 壁 (a thick wall), or 厚い 布 (thick cloth).
分厚い (buatsui) — very thick, bulky, massive. The prefix 分 adds emphasis, suggesting an extraordinary or noticeable thickness, such as a 分厚い 辞書 (a very thick dictionary).
厚着 (atsugi) — thick clothing, dressing warmly. This noun refers to wearing many or heavy layers of clothes, typically to stay warm in cold weather.
手厚い (teatsui) — cordial, warm, generous, elaborate. This adjective often describes generous treatment or care. For instance, 手厚い 看護 (generous nursing care) or 手厚い 歓迎 (a warm welcome).
Common Words & Compounds
The kanji 厚 is a key component in Japanese vocabulary, appearing in numerous compound words. These words expand on its core meanings of "thickness," "depth," "kindness," and "generosity." Understanding these compounds will significantly boost your ability to understand and use Japanese naturally.
Words related to Physical Thickness and Dimension:
厚さ (atsusa) — thickness, depth. This noun measures or describes the extent of something from one surface to another. For example, 「紙の厚さはどれくらいですか？」 (What is the thickness of the paper?)
厚み (atsumi) — thickness, depth, bulk. Similar to 厚さ, but often carries a nuance of volume or substance. It can also refer to the "depth" or "richness" of content or character, as in 人間性に厚みがある (to have depth of character).
肉厚 (nikuatsu) — thick-fleshed, stout, robust. This term is often applied to vegetables or fruits with substantial flesh (e.g., 肉厚のピーマン - a thick-fleshed bell pepper). It can also describe something sturdy or robust.
厚切り (atsugiri) — thick slice. This refers to food items cut into generous, thick portions, such as 厚切りベーコン (thick-sliced bacon) or 厚切りトースト (thick-sliced toast). It contrasts with 薄切 (usugiri - thin slice).
厚板 (atsuita) — thick board, plank. A straightforward compound for a piece of wood that is notably thick.
Words related to Warmth, Kindness, and Generosity:
手厚い (teatsui) — cordial, warm, generous, elaborate (treatment). This adjective describes considerate and abundant treatment. You might experience 手厚いもてなし (generous hospitality) at a traditional ryokan.
厚意 (kōi) — kindness, favor, good will. A formal term for expressing gratitude for someone's kind intentions or actions. For example, 「皆様のご厚意に心より感謝いたします」 (I sincerely thank you for everyone's kindness).
厚遇 (kōgū) — warm reception, cordial treatment, hospitality. Similar to 手厚いもてなし, this means being treated exceptionally well or respectfully. Being 厚遇される (to receive a warm welcome) is always a positive experience.
温厚 (onkō) — gentle, mild-mannered, amiable. This compound combines 温 (warm) with 厚 (kind/generous), describing a person with a warm and gentle disposition. 「彼は温厚な性格だ」 (He has a gentle personality).
Words with Figurative or Extended Meanings:
厚顔無恥 (kōganmuchi) — shamelessness, impudence, brazenness. This four-character idiom describes someone so utterly "thick-faced" (厚顔) they are without shame (無恥). It's a strong derogatory term.
厚化粧 (atsugeshō) — thick makeup, heavy makeup. This describes applying a significant amount of cosmetics, often implying an attempt to conceal flaws or achieve a dramatic look.
厚かましい (atsukamashii) — impudent, brazen, audacious. This i-adjective describes presumptuous or rude behavior, like having a "thick skin" or "thick face" in a negative sense. For example, 「厚かましいお願いですが…」 (It's a brazen request, but...).
Example Sentences
Here are some example sentences demonstrating the practical use of the kanji 厚 in various contexts:
この本はとても厚いので、読み終えるのに時間がかかるだろう。
Kono hon wa totemo atsui node, yomi-oeru noni jikan ga kakaru darō.
This book is very thick, so it will probably take a long time to finish reading.
冬は厚着をして、風邪をひかないようにしましょう。
Fuyu wa atsugi o shite, kaze o hikanai yō ni shimashō.
In winter, let's dress warmly (wear thick clothes) so we don't catch a cold.
彼女の厚意に感謝し、私は深く感動した。
Kanojo no kōi ni kansha shi, watashi wa fukaku kandō shita.
I was deeply moved and grateful for her kindness.
来客を手厚くもてなすことは、日本の文化の一部です。
Raikyaku o teatsuku motenasu koto wa, Nihon no bunka no ichibu desu.
Treating guests with warm hospitality is a part of Japanese culture.
このステーキは厚切りで、とてもジューシーで美味しい。
Kono sutēki wa atsugiri de, totemo jūshī de oishii.
This steak is thick-sliced, very juicy and delicious.
彼の知識は厚く、どんな質問にも答えられる。
Kare no chishiki wa atsuku, donna shitsumon ni mo kotaerareru.
His knowledge is profound, and he can answer any question.
先生はいつも生徒に対して温厚で、みんなから慕われている。
Sensei wa itsumo seito ni taishite onkō de, minna kara shitawarete iru.
The teacher is always gentle towards the students and is admired by everyone.
その壁はとても厚いので、外の音がほとんど聞こえません。
Sono kabe wa totemo atsui node, soto no oto ga hotondo kikoemasen.
That wall is very thick, so you can hardly hear any outside noise.
Memory Tip
To remember 厚, let's visualize its components. The top part, 厂 (gake), looks like a cliff or a protective roof. Below it, you see elements resembling 日 (sun/day) and 子 (child). Imagine a little child (子) under a sturdy cliff (厂), basking in the warm sun (日). This safe, nurturing environment allows the child to grow strong, healthy, and 'thick' in both spirit and body. The cliff provides a 'thick' shelter, and the child's well-being fosters 'thick' or 'deep' feelings of warmth and kindness. So, remember: a child under a cliff in the sun becomes thick, warm, and kind. This mnemonic links the physical thickness, the sense of protection and depth, and the metaphorical meaning of warmth and kindness, helping you recall all aspects of 厚.