Synonyms for Cowboy (same or very similar meaning)
WordNet sense 1 (a performer who gives exhibitions of riding and roping and bulldogging):
rodeo rider
WordNet sense 2 (a hired hand who tends cattle and performs other duties on horseback):
cattleman, cowhand, cowherd, cowman, cowpoke, cowpuncher, puncher
From the ODE community, based on WordNet
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