Meaning
The kanji 同 (dō/ona-ji) primarily conveys the meaning of 'same,' 'equal,' or 'agree.' It describes situations where two or more things are alike, identical, or share a common characteristic or state. Additionally, it can imply a sense of 'togetherness' or 'unison,' especially for actions or conditions shared by multiple entities, whether performed simultaneously or in agreement.
Its origin is generally considered an ideograph—a character that conveys meaning through a combination of existing graphic elements. While interpretations vary, a common explanation suggests it depicts a mouth (口) within an enclosure or boundary (冂). This visual arrangement can be interpreted in a few ways: 'everyone in the same space speaks with one voice,' or 'all gathered together expressing the same idea.'
The enclosure visually brings elements into a singular, unified space, and the mouth represents expression or opinion. Together, these elements lead to the core ideas of sameness and agreement. This visual shape effectively connects to its meaning: a contained group (冂) all saying the same thing (口), or perhaps two identical elements enclosed within a boundary. The simplicity of its form holds deep core concepts. As a 2nd-grade kanji with 6 strokes, 同 is introduced relatively early in a Japanese student's kanji learning journey.
Readings
On'yomi (音読み) — Chinese-derived readings
The primary On'yomi reading for 同 is ドウ (dō). This reading is frequently used when 同 forms part of a compound word, signifying 'same,' 'together,' 'agreement,' or 'similarity.' It appears in many essential vocabulary words.
同意 (dōi) — agreement, consent. This compound combines 同 (same, agree) with 意 (mind, intention), literally meaning 'same intention' or 'agreement.' For example, when asking for 同意 for a proposal.
同時 (dōji) — simultaneous, at the same time. Here, 同 (same) is combined with 時 (time), meaning 'same time.' Think of 同時 発売 (simultaneous release) for products.
共同 (kyōdō) — cooperation, collaboration, working together. This word pairs 共 (together) with 同 (same, agree), emphasizing shared effort and objectives, like in 共同 作業 (collaborative work).
同梱 (dōkon) — enclosed (together). Often used in shipping or packaging, combining 同 (together) with 梱 (bundle, pack). For instance, when an invoice is 同梱 with a product.
Kun'yomi (訓読み) — Native Japanese readings
The main Kun'yomi reading for 同 is おな(じ) (ona-ji). This functions as a standalone adjective meaning 'same' or 'identical' and is highly common in daily conversation and writing, directly applying the kanji's core meaning.
同じ (onaji) — same, identical, similar. This is the most direct and common usage, almost always followed by a noun or used predicatively.
同じ色 (onaji iro) — the same color. For example, "That car is the 同じ色 as mine."
同じ意見 (onaji iken) — the same opinion. Used when people share views, e.g., "We have the 同じ意見 on this matter."
同じ場所 (onaji basho) — the same place. As in, "Let's meet at the 同じ場所 as last time."
Common Words & Compounds
The kanji 同 appears in numerous compound words, crucial for expressing concepts of sameness, agreement, and togetherness. Categorizing these compounds can help you better grasp their nuanced meanings.
Time and Location
同時 (dōji) — simultaneous, at the same time. Essential for describing events happening concurrently, such as 同時 多発 (simultaneous occurrence of multiple events).
同年 (dōnen) — same year. Often used to refer to events or people from the same calendar year, for instance, 同年 卒業 (graduating in the same year).
同日 (dōjitsu) — same day. Frequently seen in news reports or formal documents referring to events on the same date. Example: 同日 午後 (on the afternoon of the same day).
同居 (dōkyo) — living together. Implies sharing a residence with another person or people, like in 同居 家族 (family living together).
同席 (dōseki) — sitting together, sharing a seat/table. Common in formal settings or dining. For example, 社長と同席する (to sit at the same table as the president).
Agreement and Collaboration
同意 (dōi) — agreement, consent, approval. A key word for expressing accord. For example, 契約に同意する (to agree to a contract).
共同 (kyōdō) — cooperation, collaboration, joint (effort). Emphasizes working together towards a shared goal, such as 共同 開発 (joint development).
賛同 (sandō) — approval, endorsement, agreement with. Used when one supports an idea or proposal. For instance, 提案に賛同する (to endorse a proposal).
同感 (dōkan) — same feeling, sympathy, agreement. Expresses sharing the same emotion or sentiment. A common phrase is 「私も同感です」 ("I feel the same way.").
同志 (dōshi) — comrade, kindred spirit, like-minded person. Refers to people who share the same ideals or goals. For instance, 政治的 同志 (political comrades).
Equality and Similarity
同等 (dōtō) — equality, equivalence, same rank. Denotes equal status or value. For example, 専門家と同等の知識 (knowledge equal to an expert's).
同一 (dōitsu) — identical, same (often for abstract concepts or exact sameness). Stronger than just 'same,' implying absolute identity, such as 同一人物 (the identical person).
同級生 (dōkyūsei) — classmate (student of the same grade). A common term for peers in an academic setting. "My 同級生 from high school."
同性 (dōsei) — same sex/gender. Used in discussions about gender or relationships, e.g., 同性婚 (same-sex marriage).
同色 (dōshoku) — same color. Simple and direct, used to describe identical colors. "These two shirts are 同色."
Example Sentences
私たちは同じクラスです。
Watashitachi wa onaji kurasu desu.
We are in the same class.
この二つの本は同じテーマについて書かれています。
Kono futatsu no hon wa onaji tēma ni tsuite kakareteimasu.
These two books are written about the same theme.
彼と私は同じ意見です。
Kare to watashi wa onaji iken desu.
He and I have the same opinion.
会議で皆が同意しました。
Kaigi de mina ga dōi shimashita.
Everyone agreed at the meeting.
私たちは同じ目標を持って共同で作業しています。
Watashitachi wa onaji mokuhyō o motte kyōdō de sagyō shiteimasu.
We are working together with the same goal.
両社は同時に新製品を発表しました。
Ryōsha wa dōji ni shinseihin o happyō shimashita.
Both companies announced new products simultaneously.
彼は私の大学の同級生です。
Kare wa watashi no daigaku no dōkyūsei desu.
He is my university classmate.
この二つの意見はほぼ同一だと考えられます。
Kono futatsu no iken wa hobo dōitsu da to kangaeraremasu.
These two opinions can be considered almost identical.
あなたは私と同感ですか。
Anata wa watashi to dōkan desu ka?
Do you agree with me (share the same feeling)?
Related Kanji
- 弟 — Younger Brother, Junior (Kanji N4)
- 以 — By Means Of, With, From (Kanji N4)
- 黒 — Black, Dark (Kanji N4)
- 洗 — Wash (Kanji N4)
- 短 — Short, brief, defect (Kanji N4)
- 田 — Rice Field (Kanji N4)
Memory Tip
To remember 同 (dō/ona-ji), visualize its components: an enclosure or boundary (冂) and a mouth (口). Picture a scenario where everyone gathered within the same enclosure (冂) is speaking with the same voice (口), or expressing their agreement. This image of shared expression—a mouth inside a box—directly conveys the meaning of 'same' or 'agree.' Imagine a group of people in a meeting, all nodding their heads and saying "yes" in unison. They share the 'same' opinion and are 'together' in their agreement.