blackthorn vs pear hawthorn

blackthorn and pear hawthorn both are nouns.

Word	Noun	Adjective	Verb	Adverb
blackthorn	Yes	No	No	No
pear hawthorn	Yes	No	No	No

As nouns, blackthorn and pear hawthorn are synonyms defined as:

blackthorn and pear hawthorn: erect and almost thornless American hawthorn with somewhat pear-shaped berries

Other synonyms of blackthorn include Crataegus calpodendron, Crataegus tomentosa, pear haw.

blackthorn (noun)	pear hawthorn (noun)
erect and almost thornless American hawthorn with somewhat pear-shaped berries	erect and almost thornless American hawthorn with somewhat pear-shaped berries
a thorny Eurasian bush with plumlike fruits