Meaning
功 means achievement, merit, success, and distinguished service. It names the recognized result of genuine, sustained effort — the honor given to someone who contributed significantly, excelled under real pressure, or served faithfully for years. From a samurai's valor on the battlefield to a scientist's groundbreaking discovery to an employee's decades of quiet dedication, 功 captures that earned, publicly acknowledged distinction.
Structurally, 功 is a compound ideograph (kaii, 会意) built from two components: 工 on the left, meaning "craft" or "skilled work," and 力 on the right, meaning "power" or "physical strength." Together they suggest strength applied to skilled labor. When genuine ability meets genuine effort, something meritorious results. That visual logic — work plus strength equals achievement — makes 功 easy to remember.
At just 5 strokes, 功 is a Grade 4 kanji (教育漢字, kyōiku kanji), taught in the fourth year of primary school. Simple in form, it carries real cultural weight in Japanese society — showing up wherever honor, seniority, public service, or institutional recognition is at stake. Its radical is 力 (ちから, "strength"), keeping the theme of effort visible in the character's structure.
Readings
On'yomi (音読み) — Chinese-derived readings
功 has two on'yomi: コウ (kō) and ク (ku). Both were borrowed from Chinese at different historical periods, and both appear in compound words (熟語, jukugo) rather than in isolation.
コウ (kō) is the dominant modern reading. It turns up in the great majority of contemporary compounds — newspapers, formal writing, and everyday conversation alike. It covers achievement, contribution, and the successful outcome of applied effort.
- 成功 (seikō) — success, achievement; the most widely used compound with this kanji
- 功績 (kōseki) — distinguished service, meritorious achievement, contribution
- 功労 (kōrō) — meritorious service, long-term contribution deserving recognition
ク (ku) is an older reading, surviving mainly in Buddhist vocabulary and certain classical or ceremonial expressions. Rare in casual Japanese, it surfaces in religious and cultural contexts tied to the idea of accumulated spiritual merit.
- 功徳 (kudoku) — virtuous deed, merit (a core Buddhist concept: good karma earned through righteous action)
- 功力 (kuriki) — power of accumulated virtue or spiritual merit (Buddhist term)
Kun'yomi (訓読み) — Native Japanese readings
The kun'yomi reading of 功 is いさお (isao). Rarely seen in everyday Japanese, it appears almost entirely in personal names and classical literary contexts. It refers to a deed of valor — a formally recognized act of distinguished merit. The word predates widespread Chinese loanword adoption into Japanese, reflecting how the language expressed honored achievement before Chinese vocabulary reshaped it.
- 功 (isao) — meritorious deed, distinguished achievement (names and classical texts)
Isao appears regularly as a masculine given name — 田中功 (Tanaka Isao), for instance — evoking traditional honor, accomplishment, and moral virtue. Recognizing it in names and historical narratives is valuable for advanced learners, even if writing it in prose is uncommon.
Common Words & Compounds
功 spans a wide range — everyday professional Japanese through formal, historical, and Buddhist registers. Compounds below are grouped by theme.
Success and Achievement:
- 成功 (seikō) — success; the most common compound using 功 in modern Japanese
- 功績 (kōseki) — achievement, contribution, distinguished service officially recognized
- 功名 (kōmyō) — fame earned through a notable achievement; glory won in action
- 武功 (bukō) — military achievement, valor on the battlefield
- 勲功 (kunkō) — decorated achievement, distinguished service meriting an official award
Service and Contribution Over Time:
- 功労 (kōrō) — meritorious service, contribution sustained over years
- 功労者 (kōrōsha) — a person of distinguished or meritorious service
- 年功 (nenkō) — seniority; accumulated merit from years of faithful service
- 年功序列 (nenkō joretsu) — the seniority system; the traditional Japanese workplace principle where rank and pay rise with years of service
Merits, Faults, and Utility:
- 功罪 (kōzai) — merits and faults; the pros and cons of something weighed together
- 功過 (kōka) — merits and demerits considered together
- 功利 (kōri) — utility, practical benefit; often appears in 功利主義 (utilitarianism)
Buddhist and Classical Terms:
- 功徳 (kudoku) — merit, virtuous deed; in Buddhist thought, the positive spiritual energy built up through good actions
- 功力 (kuriki) — the power of accumulated spiritual merit or virtue
Example Sentences
このプロジェクトは見事に成功した。
Kono purojekuto wa migoto ni seikō shita.
This project came off brilliantly.
彼女の功績は広く認められた。
Kanojo no kōseki wa hiroku mitomerareta.
Her contributions were widely recognized.
彼は会社への長年の功労を称えられた。
Kare wa kaisha e no naganen no kōrō wo tataerareta.
He was recognized for his years of dedicated service to the company.
年功序列は日本の伝統的な職場制度だ。
Nenkō joretsu wa Nihon no dentōteki na shokuba seido da.
The seniority system is a traditional Japanese workplace institution.
功罪を冷静に判断することが大切だ。
Kōzai wo reisei ni handan suru koto ga taisetsu da.
Calmly weighing the pros and cons is what matters.
彼は戦場で武功を立てた。
Kare wa senjō de bukō wo tateta.
He made his name on the battlefield.
成功するためには地道な努力が必要だ。
Seikō suru tame ni wa jimichi na doryoku ga hitsuyō da.
Success takes steady, unglamorous effort.
彼女は功名を求めて困難な道を選んだ。
Kanojo wa kōmyō wo motomete konnan na michi wo eranda.
She chose the hard road, chasing glory.
その僧の功徳は多くの人に伝わった。
Sono sō no kudoku wa ōku no hito ni tsutawatta.
The monk's good deeds touched many people.
その科学者の功績は後世にわたって語り継がれた。
Sono kagakusha no kōseki wa kōsei ni watatte kataritsugareta.
The scientist's legacy was told and retold for generations.
Memory Tip
Picture a craftsman (工) driving his full strength (力) into his work. 工 is the skilled worker — the trade, the technique, the disciplined hand. 力 is the raw effort behind every blow. When those two combine, something extraordinary results: a masterwork others stop to recognize. That masterwork is his 功.
Lock it to 成功 (seikō, "success"), and the meaning holds: 功 is not the result handed to you — it's the effort that earns it.