成 員(せいいん)

せいいん

noun

member; constituent

1. member; constituent

A person who belongs to and forms part of a group, organization, or society. More formal and academic than everyday words for 'member.'

家族(かぞく)の成員(せいいん)それぞれに役割(やくわり)がある。

Each member of the family has a role.

社会(しゃかい)の成員(せいいん)として責任(せきにん)を果(は)たす。

To fulfill one's responsibility as a member of society.

組織(そしき)の成員(せいいん)が増(ふ)えるにつれて意思(いし)決定(けってい)が難(むずか)しくなる。

As the number of members in the organization grows, decision-making becomes more difficult.

A formal, somewhat academic term for a member or constituent of a group. Most commonly encountered in sociology, political science, and formal writing. Unlike 会員(かいいん), which implies formal enrollment, 成員(せいいん) emphasizes being a constituent part of a collective.

Common collocations

社会(しゃかい)の成員(せいいん): member of society
家族(かぞく)の成員(せいいん): family member
組織(そしき)の成員(せいいん): member of an organization
集団(しゅうだん)の成員(せいいん): member of a group

Similar words

メンバー: member — casual loanword used in everyday speech
会員(かいいん): member — implies formal registration or membership (in a club, association, etc.)
構成員(こうせいいん): constituent member — more technical, emphasizes the structural role within an organization
一員(いちいん): one member (of) — emphasizes being part of a larger whole

Related Words

Compare: メンバー (member)

Compare: 会員(かいいん) (member)

Compare: 一員(いちいん) (one member)

general

Added 2026.4.29 22:32 · Revised 2026.9.2 13:02

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