1An organizational unit within a company or government office. In a typical Japanese corporate hierarchy (事業部 'business unit' > 部 > 課 > 係), 部 sits between 課 (smaller) and 局 (larger; used mainly in central government). Combined with a domain name to label functional areas: 営業部 (sales department), 経理部 (accounting), 開発部 (R&D). Its head is the 部長 (department head), and members are referred to as e.g. 「営業部の田中さん」.
営業部に異動になりました。
I've been transferred to the sales department.
詳しいことは経理部に確認してください。
Please check with the accounting department for the details.
うちの会社では、開発部と営業部の連携がうまくいっていない。
At our company, coordination between R&D and Sales isn't going well.
2An extracurricular club at a school or university. 部活 (= 部活動, club activities) is a central part of Japanese middle-school, high-school, and university life, broadly split into sports clubs (テニス部, 野球部, バスケ部) and culture clubs (吹奏楽部, 美術部, 茶道部). Students not in any club are jokingly called 帰宅部 ('Going-Home Club'). Used in expressions like 部に入る (join a club), 部をやめる (quit), 部活で忙しい (busy with club).
高校では吹奏楽部に入っていました。
In high school I was in the brass band club.
うちの息子はサッカー部の練習で毎日くたくただ。
My son is exhausted every day from soccer-club practice.
「部活、何やってるの？」「うーん、帰宅部かな。」
'What club are you in?' 'Hmm, I guess the Going-Home Club.'
3A part or section of a larger whole. Covers physical zones (北部 'northern part', 南部 'southern part', 上部 'upper part', 下部 'lower part') and abstract subdivisions (the first 部 of a book, 写真の一部 'part of the photo', 組織の上層部 'the upper levels of the organization'). Contrasts with 全部 ('the whole') and most often appears inside compounds like 一部の人 ('some people') or 上部組織 ('the parent organization').
日本の北部は冬になると雪が多い。
Northern Japan gets a lot of snow in winter.
この件に反対しているのは、ごく一部の人だけです。
Only a small minority is opposing this matter.
小説の第三部で物語が大きく動き出す。
The story really kicks into gear in Part 3 of the novel.
4A category or division used for classification — in contests, exhibitions, or formal documents. Common in event divisions like 年齢別の部 (age-bracket divisions), 初心者の部 (beginners' division), 自由部門 (free/open category), and in document structure (第一部, 第二部 for major book parts).
コンテストは小学生の部と中学生の部に分かれている。
The contest is split into an elementary-school division and a middle-school division.
彼は社会人の部で優勝した。
He won in the adult/working-professional category.
5A counter for copies of printed material — books, magazines, newspapers, reports, etc. Read as ぶ. Used mainly in printing, distribution, and publishing contexts; in casual speech 冊 (さつ) is often used instead, so 部 feels slightly more formal. Common in phrases like 初版2万部 ('an initial print run of 20,000'), 100部限定 ('limited to 100 copies'), 論文を3部提出する ('submit three copies of the paper').
この本の初版は5万部だった。
The first print run of this book was 50,000 copies.
会議の資料を10部用意してください。
Please prepare ten copies of the meeting materials.
限定500部のサイン本を予約した。
I pre-ordered a signed book limited to 500 copies.