The plug body itself is the "male" but the "male" parts of the actual electrical connections (the "pins") are in the "female" socket on the truck.
So it kinda is a "female cradle for a male plug."
If you really want to get confused look at a 4-pin. There are three males and a female on one half of the connector, and three females and a male on the other. Talk about a gender identity crisis...
Putting 10-ply tires on half ton trucks since aught-four.