joinder

noun

1. the act of joining.
2. Law.
   1. the joining of causes of action in a suit.
   2. the joining of parties in a suit.
   3. the acceptance by a party to an action of an issue tendered.

noun

1. the act of joining, esp in legal contexts
2. law
   1. (in pleading) the stage at which the parties join issue (joinder of issue)
   2. the joining of two or more persons as coplaintiffs or codefendants (joinder of parties)
   3. the joining of two or more causes in one suit