| Noun | 1. | Siberian crab apple - Asian wild crab apple cultivated in many varieties for it small acid usually red fruit used for preservinggenus Malus, Malus - apple trees; found throughout temperate zones of the northern hemisphere crab apple, crabapple, cultivated crab apple - any of numerous varieties of crab apples cultivated for their small acid (usually bright red) fruit used for preserving or as ornamentals for their blossoms | |