According to this glossary, http://checc.sph.unc.edu/rooms/school/whole_hog/glossary.html

Boar - A male hog used for breeding purposes. Boars weigh about 500 pounds.

Farrow - A litter of pigs; giving birth. The hog industry uses the expression "Farrow to Finish" to describe operations that contain pigs from birth to market ready.

Feeder pig - A weaned pig up to about 10 to 12 weeks of age, weighing 40 to 50 pounds. Feeder pigs are brought to market weight during the finishing process

Piglet - Common term for a baby pig.

Sow - A female hog used for breeding purposes. Sows generally weigh between 450 and 500 pounds. Some hog operations specialize in handling sows and their litters only.

Swine - Another term for hog.

The glossary does not define "hog," but the implication of the definitions of "boar" and "sow" is that "hog" encompasses both sexes and describes a domesticated pig raised for food. I will try to remember to call my pig-farmer friend for more explication.