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late 14c., "power, efficacy," from Old French actualite and directly from Medieval Latin actualitatem (nominative actualitas), from Late Latin actualis (see actual). A Latin loan-translation of Greek energeia. Meaning "state of being real" is from 1670s (actualities "existing conditions" is from 1660s).
Mod. use of actuality in the sense of realism, contact with the contemporary, is due to Fr. actualité, from actuel, which does not mean actual, real, but now existing, up to date. [Weekley]