Noun | 1. | ![]() rosid dicot genus - a genus of dicotyledonous plants family Rosaceae, Rosaceae, rose family - a large family of dicotyledonous plants of order Rosales; have alternate leaves and five-petaled flowers with numerous stamens medlar tree, Mespilus germanica, medlar - small deciduous Eurasian tree cultivated for its fruit that resemble crab apples |