luottamusmies

Noun

 * 1) union representative, union steward,  shop steward,  workplace steward
 * 2)  A union representative whose powers are based on a collective agreement between an employers' association and a trade union, as contrasted with luottamusvaltuutettu.

Usage notes
Despite containing the word the term can be used for both males and females. A corresponding gender-neutral term is, whereas can be used only for females.