an organization of workers formed to protect and improve, through all collective action, the social, economic and political interests of its members, workers organized into a voluntary association, or union, to further their mutual interests with respect to wages, hours, working conditions and other matters of interest to the workers, iseseisev omaalgatuslik ja vabatahtlik isikute ühendus, mille eesmärgiks on töötajate töö-, teenistus- ja kutsealaste, majanduslike ning sotsiaalsete õiguste ja huvide esindamine ning kaitsmine