Trade union
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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Labor Organization
Any organization of any kind, or any agency or employee representation committee or plan, in which employees participate and which exists for the purpose, in whole or in part, of dealing with employers concerning grievances, labor disputes, wages, rates of pay, hours of employment, or conditions of work. 29 USC