Technical Abstract: The name Celtis glabrata is technically illegitimate and has nomenclatural priority over U. glabra and should be replaced under the international rules of botanical nomenclature. The replacement name Celtis planchoniana, proposed in 1997 but seldom adopted to date, is not the correct name for this species under the rules, and the name that is technically correct (Celtis kotschyana) has not been used in over 150 years. Accurate communication of horticultural information, research results, and other information about these plants requires a stable, well documented nomenclature, and resurrecting this long-disused name would simply cause confusion when communicating information about this species. Past and present nomenclature of this species are examined and documented. The best solution is to formally conserve the name Celtis glabrata, and it is formally proposed that this be done by the International Association for Plant Taxonomy, the international authority for plant nomenclature. This will allow botanists to continue to use a name that is well established and unambiguous, ensuring clear and accurate dissemination of information about this species, which is being grown at the National Arboretum and evaluated for its nursery potential.