plantsman vs gardener

plantsman and gardener both are nouns.

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

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

plantsman: an expert in the science of cultivating plants (fruit or flowers or vegetables or ornamental plants)
gardener: someone who takes care of a garden

Other hyponyms of plantsman include nurseryman.

plantsman (noun)	gardener (noun)
an expert in the science of cultivating plants (fruit or flowers or vegetables or ornamental plants)	someone who takes care of a garden
	someone employed to work in a garden