Celtis cel·tis uncommon noun 1. large genus of trees and shrubs with berrylike fruit Synonymsgenus Celtis Related words Word family Celtis australisCeltis laevigataCeltis occidentalis Broader terms dicot genus Parts Ulmaceae Part of hackberryEuropean hackberryAmerican hackberrysugarberry WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.