Active means busy doing things, or working rather than idle. An active child, an active volcano, still active.
The precise uses are technical: an active volcano is one that has erupted in recorded history, and an active ingredient is the part of a medicine that does the work. In grammar the active voice puts the doer first, which is why it reads more directly than the passive.
1adjectiveactiveBusy doing things; working rather than idle.
“My grandmother is still very active and goes swimming three times a week.”
active is a quality of doing.
Latin activus comes from agere, to do or drive. Agent and act come from the same doing.
Proto-Indo-European
*h₂eǵ-
Middle English
actyf
English, today
active
Built from
From Middle English actyf. From Middle English actyf, from Old French actif, from Latin activus, from ago (“to do, to act”), ultimately from Proto-Indo-European h₂éǵeti. by surface analysis, en + act + ive.
Etymology from Wiktionary, CC BY-SA