orange vs orange tree

orange and orange tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
orange	Yes	Yes	No	No
orange tree	Yes	No	No	No

As nouns, orange and orange tree are synonyms defined as:

orange (noun)	orange tree (noun)
orange color or pigment; any of a range of colors between red and yellow	any citrus tree bearing oranges
round yellow to orange fruit of any of several citrus trees
any citrus tree bearing oranges
any pigment producing the orange color

orange (adjective)	orange tree (adjective)
of the color between red and yellow; similar to the color of a ripe orange