trade union

from WordNet (r) 3.0 (2006)

trade union
    n 1: an organization of employees formed to bargain with the
         employer; "you have to join the union in order to get a
         job" [syn: {union}, {labor union}, {trade union}, {trades
         union}, {brotherhood}]

from The Collaborative International Dictionary of English v.0.48

trades union \trades" un`ion\, or Trade union \Trade" un`ion\ .
   An organized combination among workmen for the purpose of
   maintaining their rights, privileges, and interests with
   respect to wages, hours of labor, customs, etc.
   [1913 Webster] Trades-unionist