OB

おーびー
noun
male alumnus; graduate; former member
academiceducationsociety
1. male alumnus; male graduate; (loosely) any graduate or former member
A male former member of a school, club, or organization. From English 'old boy', a British term for male alumni. In practice OB is often used loosely for graduates or former members of either sex, as in OB会(かい) (alumni association).
OBが来校(らいこう)した。
Alumni visited the school.
野球部(やきゅうぶ)のOBが指導(しどう)に来(き)た。
Baseball club alumni came to coach.
OB会(かい)に参加(さんか)した。
I attended the alumni association meeting.

Etymology

Abbreviation of English 'old boy', a British term for male alumni. Adopted in Japan primarily for school and club contexts.

Usage

Commonly used for:

  • School alumni (especially sports clubs)
  • Company former employees
  • Organization former members

Strictly, OB means a male graduate, and the female equivalent is OG ('old girl'). In practice OB is often used loosely for graduates or former members of either sex: an OB会(かい) usually welcomes women too. When both are meant explicitly, people say OB・OG.

Compounds

  • OB会(かい) - alumni association
  • OB戦(せん) - alumni game/match
  • OB訪問(ほうもん) - visiting alumni (for job hunting advice)

Related words

  • OG - female alumna

Related Words

Related: OG (female equivalent)
general
Added 2026.1.21 9:23 · Revised 2026.10.5 22:48
07500/07715_oobii