union

union /ˈjuːnjən/ noun
plural unions
union
/ˈjuːnjən/
noun
plural unions
Britannica Dictionary definition of UNION
1 
[count] : an organization of workers formed to protect the rights and interests of its members
— called also (US) labor union, (British) trade union
2 
[noncount] : an act of joining two or more things together
3 
[singular] : a group of states or nations that are ruled by one government or that agree to work together
4 
the Union
a  : the United States
◊ The State of the Union address is a yearly speech given by the U.S. President to Congress and the people to tell them about important things that are affecting the country.
b  : the group of northern states that supported the federal government during the American Civil War
— often used as Union before another noun
5 
[count] : an organized group of people, businesses, etc., that have the same purpose or interest
— see also student union
6 
formal : the act of getting married or of causing two people to be married
[noncount]
[count]
— see also civil union
7 
[count, noncount] formal : the activity or an act of having sex