1. To become part of; become a member of a group or organization; SYN. fall in, get together.
2. To cause to become joined or linked; SYN. bring together.
3. To come into the company of.
4. To make contact or come together; SYN. conjoin.

A relational operator that combines data from multiple tables into a single result table.
1. A database table operation that creates a resultant entry in another table for each entry in the one table whose key field matches that of an entry in the other. See also inner join.
2. A multiprocessing command that causes a child process to return control to its parent. See also child (definition 1), multiprocessing.