noun (used with a singular verb)
the study of the origin, history, and use of proper names.
Origin of onomastics
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(functioning as singular) the study of proper names, esp of their origins
(functioning as singular or plural) a systematization of the facts about how proper names are formed in a given language
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Online Etymology Dictionary, © 2010 Douglas Harper