Entry 1 sense Webster, 1913 Nomenclatural /nōm-ən-klāch'-ẽr-əl/ · No·men·cla·tur·al · IPA /noʊmənklˈeɪtʃərəl/ 01 a. Pertaining or according to a nomenclature. 1. Pertaining or according to a nomenclature.