Nuances between the various words for "member"


What are the nuances between 一員, 会員, 成員, and メンバー? There is [a goo thesaurus
page](https://dictionary.goo.ne.jp/thsrs/6992/meaning/m0u/), but it didn't
really help me actually distinguish the differences.




Somewhat strangely, メンバー may be the most neutral and versatile. Also it
sometimes means _regular members_ in sports like メンバーから外される ( _removed from
regular lineup_ ).

会員's basic connotation is being registered or listed in a group of people. For
example, a user of a credit card is called カード会員; using amazon prime means you
are a アマゾンプライム会員 (though non-prime users won't be usually called アマゾン会員). Of
course, it is used to mean a member of groups with name ・・・の会.

成員 is also a member, where the group of people is less specific (less clearly
defined). It means 'a member constituting a body' rather than 'registered
member', and sounds more formal than the others. For example, 社会の成員 or 組織の成員
means a member of society/organization. Here 会員 is not possible and using メンバー
is less idiomatic.

一員 is exactly like _**a** member_ with indefinite article. Basically it is the
same usage as 一個人, emphasizing 'one-of-the many' nature of the person. It
means the same as 成員, but 一員 is usually not a subject.

  * 社会の一員/成員になる _become a member (part) of the society_
  * 組織の各成員が全力を尽くす _Each member of the organization does her best._ 各一員 is not possible.

It is often used with として: 会社の一員としての責任 _responsibility as a member of the
company_.




Somewhat strangely, メンバー may be the most neutral and versatile. Also it
sometimes means _regular members_ in sports like メンバーから外される ( _removed from
regular lineup_ ).

会員's basic connotation is being registered or listed in a group of people. For
example, a user of a credit card is called カード会員; using amazon prime means you
are a アマゾンプライム会員 (though non-prime users won't be usually called アマゾン会員). Of
course, it is used to mean a member of groups with name ・・・の会.

成員 is also a member, where the group of people is less specific (less clearly
defined). It means 'a member constituting a body' rather than 'registered
member', and sounds more formal than the others. For example, 社会の成員 or 組織の成員
means a member of society/organization. Here 会員 is not possible and using メンバー
is less idiomatic.

一員 is exactly like _**a** member_ with indefinite article. Basically it is the
same usage as 一個人, emphasizing 'one-of-the many' nature of the person. It
means the same as 成員, but 一員 is usually not a subject.

  * 社会の一員/成員になる _become a member (part) of the society_
  * 組織の各成員が全力を尽くす _Each member of the organization does her best._ 各一員 is not possible.

It is often used with として: 会社の一員としての責任 _responsibility as a member of the
company_.

