cowboy vs puncher

cowboy and puncher both are nouns.

Word	Noun	Adjective	Verb	Adverb
cowboy	Yes	No	No	No
puncher	Yes	No	No	No

As nouns, puncher is a hypernym of cowboy; that is, puncher is a word with a broader meaning than cowboy:

cowboy: a male hired hand who tends cattle and performs other duties on horseback
puncher: a hired hand who tends cattle and performs other duties on horseback

Other hypernyms of cowboy include cowhand, cowherd, cowpoke, cowpuncher, adult male, man.

cowboy (noun)	puncher (noun)
someone who is reckless or irresponsible (especially in driving vehicles)	a tool for making holes or indentations
a performer who gives exhibitions of riding and roping and bulldogging	a hired hand who tends cattle and performs other duties on horseback
a male hired hand who tends cattle and performs other duties on horseback	someone who delivers punches