članica

1. member
   Moja sestra je članica gradskog hora. — My sister is a member of the city choir.
   Postala je članica upravnog odbora. — She became a member of the board.
2. (of a state, organization) member; member state
   Hrvatska je članica Evropske unije. — Croatia is a member of the European Union.
   Sastanku su prisustvovale sve zemlje članice. — All member states attended the meeting.

Also used with feminine nouns like zemlja or stranka: zemlja članica 'member state'.