表層形
行為
コーイ
名詞
行為 (コーイ)
Koui · こーい — act, deed, conduct
Other ways to say “act” in Japanese →
行為 in rōmaji: koui, also spelled koi.
名詞
普通名詞
一般
*
🔤 * 📐 *
Updated: 2026年8月13日
📖 Grammar Information
| 表層形 (Surface) |
行為
|
|---|---|
| 読み (Reading) |
コーイ
|
| 品詞 (POS) |
名詞・普通名詞・一般・*
|
| 活用型 (Conj. Type) |
*
|
| 活用形 (Conj. Form) |
*
|
| 表記 (Orthography) |
行為
|
| 読み・基本形 |
コーイ
|
| 表記・基本形 |
行為
|
| 見出し語の読み |
コウイ
|
💡 English Meaning
行為 means “act, deed, conduct” — full definition & examples →
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行為
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Reading & Info
コーイ
名詞普通名詞一般*
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Did you know · 名詞
名詞 (nouns) are the backbone of Japanese sentences. They can be combined with particles like が, を, に, で to indicate grammatical role.
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❓ About this entry
What is the difference between surface form and lemma? ▼
The surface form (行為) is the exact text as it appeared in the corpus — it may be conjugated or inflected. The lemma (行為) is the dictionary base form. For example, 食べた (surface) has the lemma 食べる.
What does the reading (pron) field mean? ▼
The reading shows the pronunciation in hiragana or katakana as recorded by UniDic. For kanji entries this is the standard reading of this specific surface form — which may differ from other readings of the same kanji.
What is UniDic? ▼
UniDic is a comprehensive Japanese lexicon developed by the National Institute for Japanese Language and Linguistics (NINJAL). It provides detailed morphological information for modern Japanese words, used in NLP tools like MeCab.
How do I save this entry? ▼
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