sorb apple tree vs Sorbus domestica

sorb apple tree and Sorbus domestica both are nouns.

Word	Noun	Adjective	Verb	Adverb
sorb apple tree	Yes	No	No	No
Sorbus domestica	Yes	No	No	No

As nouns, sorb apple tree and Sorbus domestica are synonyms defined as:

sorb apple tree and Sorbus domestica: medium-sized European tree resembling the rowan but bearing edible fruit

Other synonyms of sorb apple tree include service tree, sorb apple.

sorb apple tree (noun)	Sorbus domestica (noun)
medium-sized European tree resembling the rowan but bearing edible fruit	medium-sized European tree resembling the rowan but bearing edible fruit