sweet orange tree vs Citrus sinensis

sweet orange tree and Citrus sinensis both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet orange tree	Yes	No	No	No
Citrus sinensis	Yes	No	No	No

As nouns, sweet orange tree and Citrus sinensis are synonyms defined as:

sweet orange tree and Citrus sinensis: probably native to southern China; widely cultivated as source of table and juice oranges

Other synonyms of sweet orange tree include sweet orange.

sweet orange tree (noun)	Citrus sinensis (noun)
probably native to southern China; widely cultivated as source of table and juice oranges	probably native to southern China; widely cultivated as source of table and juice oranges