1.the shape or manner in which things come together and a connection is made
2.a set containing all and only the members of two or more given sets;
let C be the union of the sets A and B
1.become part of; become a member of a group or organization;
He joined the Communist Party as a young man
2.cause to become joined or linked;
join these two parts so that they fit together
3.come into the company of;
She joined him for a drink
4.make contact or come together;
The two roads join here
5.be or become joined or united or linked;
The two streets connect to become a highway