gardener vs groundsman

gardener and groundsman both are nouns.

Word	Noun	Adjective	Verb	Adverb
gardener	Yes	No	No	No
groundsman	Yes	No	No	No

As nouns, groundsman is a hyponym of gardener; that is, groundsman is a word with a more specific, narrower meaning than gardener:

gardener: someone employed to work in a garden
groundsman: someone who maintains the grounds (of an estate or park or athletic field)

Other hyponyms of gardener include groundkeeper, groundskeeper, hedger.

gardener (noun)	groundsman (noun)
someone who takes care of a garden	someone who maintains the grounds (of an estate or park or athletic field)
someone employed to work in a garden