Labor union

union of workers who have joined together to protect their rights

A trade union or labour union is an organization of workers. The trade union, through its leadership, bargains with the employer on behalf of union members ("rank and file" members) and negotiates labor contracts with employers. This may include the negotiation of wages, work rules, complaint procedures, rules governing hiring, firing and promotion of workers, benefits, workplace safety and policies. The agreements negotiated by the union leaders are binding on the rank and file members and the employer and in some cases on other non-member workers.
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Noun
1. an organization of employees formed to bargain with the employer; "you have to join the union in order to get a job"
(synonym) union, trade union, trades union, brotherhood
(hypernym) organization, organisation
(hyponym) industrial union, vertical union
(part-holonym) labor movement, trade union movement, labor

n. สหภาพแรงงาน (syn. trade union, union)