join-n; 2 Senses

Sense Number 1: location where things are connected, fastened

Commentary: JOIN[+location][+spatial][+connection]

Sew a seam at the join of the sleeve to the bodice of the blouse.
There was a train collision at the join of the north-south track the east-west track.

WordNet 3.0 Sense Numbers: 1

Sense Number 2: a set containing all the members of two other sets

Commentary: JOIN[+collection][+set][+union][+mathematical]

The join of the employee database table to the manager table will show who manages each employee.
The text describes how to perform an outer join.