Siberian crab vs Siberian crab apple

Siberian crab and Siberian crab apple both are nouns.

Word	Noun	Adjective	Verb	Adverb
Siberian crab	Yes	No	No	No
Siberian crab apple	Yes	No	No	No

As nouns, Siberian crab and Siberian crab apple are synonyms defined as:

Siberian crab and Siberian crab apple: Asian wild crab apple cultivated in many varieties for it small acid usually red fruit used for preserving

Other synonyms of Siberian crab include cherry apple, cherry crab, Malus baccata.

Siberian crab (noun)	Siberian crab apple (noun)
Asian wild crab apple cultivated in many varieties for it small acid usually red fruit used for preserving	Asian wild crab apple cultivated in many varieties for it small acid usually red fruit used for preserving