Sŷnch'ro-nĭsm, n.

noun

n. [Fr. synchronisme, Gr. συγχρονισμός, from συγχρονίζειν, to be contemporary with, from σύγχρονος, synchronous, q. v.]

Concurrency of two or more events in time; simultaneousness.
The tabular arrangement of historical events and personages, according to their dates.
(Paint.) A representation of two or more events occurring at different times, in the same picture. Fairholt.