Actual means real, rather than supposed. The actual cost, in actual fact, the actual reason.
It is often filler — the actual cost is usually just the cost — and editors strike it out for that reason, though it earns its place when a contrast with the supposed is meant. In actual fact is redundant twice over. Note that the Latin actualis means active or practical, from agere, to do.
1adjectiveactualReal, rather than supposed.
“The film is based on actual events, not just the writer's imagination.”
actual is a quality of realness.
Latin actualis means active or practical, from actus, an act, from agere, to do. Agent and agile come from the same doing.
Proto-Indo-European
*h₂eǵ-
Latin
actuālis — active, practical
Anglo-Norman
actuel
Middle English
actual
English, today
actual
Built from
From Middle English actual, actuel (“active”), from Anglo-Norman actuel, actual, and its source Latin actuālis (“active, practical”), from Latin actus (“act, action, performance”), from ago (“to do; to act”) + -alis (“-al”), ultimately from Proto-Indo-European h₂éǵeti, from the root h₂eǵ-. by surface analysis, act + -u- + -al.
Etymology from Wiktionary, CC BY-SA