although it has become a synonym for cowboy and cowhand, historically it was not the same, and cowpunchers were a lower class with less skills than the cowhand. As I learned it, the word came into existence to describe those fellows who worked in the pens at the railyards and slaughterhouses. Their job was to move cows from pen to pen though gates and up ramps for loading. They were not known to be gentle about it or to have any concern for bovine welfare. Often they used poles to prod and poke the cows to overcome their reluctance to go some place that was less than appealing to the cows nature. Hence they were said to "punch" the cows through the gates and up the ramps. Any skilled cowhand would be insulted if you called him (or her) a cowpuncher and these rounders did not work from the back of a horse.