- hackberry, nettle tree - any of various trees of the genus Celtis having inconspicuous flowers and small berrylike fruits
--1 is a kind of tree
--1 is a member of Celtis, genus Celtis
--1 has particulars:European hackberry, Mediterranean hackberry, Celtis australis; American hackberry, Celtis occidentalis; sugarberry, Celtis laevigata - sugarberry, hackberry - small edible dark purple to black berry with large pits; southern United States
--2 is a kind of berry