大 — Big, Large

Meaning

The kanji 大 (おお), pronounced as 'oo' or 'dai/tai', primarily conveys the meaning of 'big', 'large', or 'great'. It's a fundamental kanji, serving as an essential building block for many other characters and Japanese concepts.

Visually, 大 is a pictograph. It originated from the depiction of a person standing with their arms and legs outstretched, vividly illustrating the idea of being 'large' or 'expansive'. This posture symbolizes something vast or grand.

Its simple form makes it easy to remember. The top horizontal stroke represents the head, while the two diagonal strokes extending downwards represent outstretched arms. The final downward stroke symbolizes the legs. This direct visual representation connects its shape to its core meaning: a person making themselves appear as large as possible. Understanding this visual origin helps you grasp its essence and how it's applied in various compound words.

The kanji 大 has just 3 strokes, making it quick to write and recognize. As a Grade 1 kanji, it's taught to children in the first year of elementary school in Japan. This highlights its high frequency and basic importance in the Japanese language. Its simplicity and core meaning make it a cornerstone for learning more complex kanji that incorporate the idea of size or significance.

Readings

On'yomi (音読み) — Chinese-derived readings

On'yomi readings are derived from Chinese pronunciations and are typically used when the kanji is part of a compound word, often with other kanji. 大 has two primary on'yomi readings: ダイ (DAI) and タイ (TAI).

ダイ (DAI)

This is the more common on'yomi reading. You'll often find it in words describing things that are 'big' in general terms, or significant in scale or importance.

大学だいがく (daigaku) — university (literally 'big' + 'learning')
大体だいたい (daitai) — generally, mostly (literally 'main part' or 'general outline')
大人気だいにんき (daininki) — very popular (literally 'big' + 'popularity')

タイ (TAI)

This reading is used in specific compound words, frequently conveying a sense of 'greatness', 'magnitude', or 'opposition'.

大切たいせつ (taisetsu) — important, valuable (literally 'great' + 'cut/set')
大会たいかい (taikai) — convention, tournament (literally 'big' + 'meet')
大気たいき (taiki) — atmosphere (literally 'big' + 'spirit/air')
大陸たいりく (tairiku) — continent (literally 'big' + 'land')

Kun'yomi (訓読み) — Native Japanese readings

Kun'yomi readings are native Japanese pronunciations. They are typically used when the kanji stands alone or is followed by okurigana (hiragana endings). 大 has several kun'yomi readings: おお-, おお.きい, and -おお.いに.

おお

(oo-)

This reading functions as a prefix, often meaning 'large' or 'many'. It directly attaches to the beginning of a word.

大勢おおぜい (oozei) — many people, large crowd
大雨おおあめ (ooame) — heavy rain
大通りおおどおり (oodōri) — main street, avenue

おお.きい (oo.kii)

This is the adjective form, meaning 'big' or 'large'. The 'きい' part is okurigana.

大きいおおきい (ookii) — big, large (used directly before a noun or as a predicate)
大きなおおきな (ookina) — large (adjectival noun, used to describe a noun, often implying a more general descriptive quality. For instance, 大きな家 (ookina ie) means a 'large house'.)

-おお.いに (-oo.ini)

This reading forms an adverb, meaning 'very much', 'greatly', or 'abundantly'.

大いにおおいに (ooini) — very, greatly, abundantly (e.g., 大いに感謝する (ooini kansha suru) means 'to be greatly thankful')

Common Words & Compounds

The kanji 大 combines with many other kanji to form a vast array of words, often related to size, importance, or extent. Here are some common examples, grouped by theme:

Size and Quantity:

大小だいしょう (daishō) — size, large and small (e.g., 大小様々な箱 (daishō samazama na hako) means 'various sized boxes')
大規模だいきぼ (daikibo) — large-scale, extensive (e.g., 大規模なプロジェクト (daikibo na purojekuto) for a 'large-scale project')
大勢おおぜい (oozei) — many people, large crowd (e.g., 大勢の人が集まった (oozei no hito ga atsumatta) means 'many people gathered')
大量たいりょう (tairyō) — large quantity, mass amount (e.g., 大量のデータを処理する (tairyō no dēta wo shori suru) to 'process a large amount of data')

Importance and Significance:

大切たいせつ (taisetsu) — important, valuable, precious
大変たいへん (taihen) — very, awfully, terribly; difficult, serious (can also mean 'great change', e.g., 大変な仕事 (taihen na shigoto) for 'a difficult job')
大人おとな (otona) — adult (literally 'big' + 'person')
大成功だいせいこう (daiseikō) — great success

Nature and Environment:

大雨おおあめ (ooame) — heavy rain
大雪おおゆき (ooyuki) — heavy snow
大気たいき (taiki) — atmosphere, air

Events and Organizations:

大会たいかい (taikai) — convention, tournament, rally
大学だいがく (daigaku) — university, college
大晦日おおみそか (oomisoka) — New Year's Eve

General Concepts:

大部分だいぶぶん (daibubun) — majority, most part
大体だいたい (daitai) — generally, mostly, outline
大抵たいてい (taitei) — mostly, usually, generally

Example Sentences

この犬いぬはとても大おおきいです。

Kono inu wa totemo ookii desu.

This dog is very big.

私わたしの夢ゆめは大おおきい家いえに住すむことです。

Watashi no yume wa ookii ie ni sumu koto desu.

My dream is to live in a big house.

日本にほんにはたくさんの大学だいがくがあります。

Nihon ni wa takusan no daigaku ga arimasu.

There are many universities in Japan.

これは私わたしにとって大切たいせつな本ほんです。

Kore wa watashi ni totte taisetsu na hon desu.

This is an important book to me.

昨日きのうは大雨おおあめが降ふりました。

Kinō wa ooame ga furimashita.

It rained heavily yesterday.

この問題もんだいは大変たいへん難むずかしいです。

Kono mondai wa taihen muzukashii desu.

This problem is very difficult.

私わたしたちは大おおきな目標もくひょうを持もっています。

Watashitachi wa ookina mokuhyō wo motteimasu.

We have a big goal.

その映画えいがは大だいヒットでした。

Sono eiga wa dai hitto deshita.

That movie was a big hit.

彼かれは大おおいに喜よろこびました。

Kare wa ooini yorokobimashita.

He was greatly pleased.

Related Kanji

Memory Tip

To remember the kanji 大, picture a stick figure of a person standing with their arms and legs spread wide, trying to appear as big as possible. The top stroke is the head, the two spreading strokes are the arms, and the bottom stroke forms the legs. This exaggerated posture directly conveys the meaning of 'big' or 'large'. Every time you see 大, imagine a person proudly exclaiming, “Look how BIG I am!” with open arms and legs. This simple, dynamic image will help you easily recall its meaning and form.