What Does It Mean?

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From our dictionary:
syn•cre•tism

(sing'kri-tiz"um, sin'-),
n.
1. the attempted reconciliation or union of different or opposing principles, practices, or parties, as in philosophy or religion.
2. Gram. the merging, as by historical change in a language, of two or more categories in a specified environment into one, as, in nonstandard English, the use of was with both singular and plural subjects, while in standard English was is used with singular subjects (except for you in the second person singular) and were with plural subjects.