Definition of pluralizer in English:
pluralizer
noun ˈplʊərəlʌɪzəˈplʊər(ə)lʌɪzəˈplɔːrəlʌɪzə
Grammar. A suffix, prefix, inflection, or auxiliary word which forms a plural.
Origin
Mid 19th century (in an earlier sense). In sense 1 from pluralize + -er.