dwarf buckeye vs buckeye

dwarf buckeye and buckeye both are nouns.

Word	Noun	Adjective	Verb	Adverb
dwarf buckeye	Yes	No	No	No
buckeye	Yes	No	No	No

As nouns, buckeye is a hypernym of dwarf buckeye; that is, buckeye is a word with a broader meaning than dwarf buckeye:

dwarf buckeye: a spreading shrub with pink flowers; found in southeastern United States
buckeye: tree having palmate leaves and large clusters of white to red flowers followed by brown shiny inedible seeds

Other hypernyms of dwarf buckeye include Aesculus hippocastanum, horse chestnut.

dwarf buckeye (noun)	buckeye (noun)
a spreading shrub with pink flowers; found in southeastern United States	tree having palmate leaves and large clusters of white to red flowers followed by brown shiny inedible seeds
	the inedible nutlike seed of the horse chestnut