crab apple

definition: small sour apple
example:
speech part: noun
synonyms: crabapple
definition: any of numerous wild apple trees usually with small acidic fruit
example:
speech part: noun
synonyms: crabapple
definition: any of numerous varieties of crab apples cultivated for their small acidic (usually bright red) fruit used for preserves or as ornamentals for their blossoms
example:
speech part: noun
synonyms: crabapple cultivated crab apple

How crab apple is being used?