cowman vs cowpoke

cowman and cowpoke both are nouns.

Word	Noun	Adjective	Verb	Adverb
cowman	Yes	No	No	No
cowpoke	Yes	No	No	No

As nouns, cowpoke is a hypernym of cowman; that is, cowpoke is a word with a broader meaning than cowman:

cowman: a male hired hand who tends cattle and performs other duties on horseback
cowpoke: a hired hand who tends cattle and performs other duties on horseback

Other hypernyms of cowman include cowhand, cowherd, cowpuncher, puncher, adult male, man.

cowman (noun)	cowpoke (noun)
a male hired hand who tends cattle and performs other duties on horseback	a hired hand who tends cattle and performs other duties on horseback