Meaning of UNION in English
[noun] [U]Union refers either to the act or the state of being joined together.Meanwhile the debate on European political and monetary union continues.(formal or old use) She believes that the union (= marriage) of man and woman in holy matrimony is for ever.A (trade) union is an organization of workers from a particular profession (= type of work) or trade which represents and protects the rights of workers within that profession and has discussions with employers over such matters as pay and working conditions.the electricians'/machinists' unionThe Union Flag is the red, white and blue flag of Great Britain.The Union Jack is (formal) the Union Flag when it is shown on a ship, or (informal) the flag of Great Britain.
Cambridge English vocab. Кембриджский английский словарь. 2012