Activity, n.; pl. Activities.
Etymology: [Cf. F. activité, LL. activitas.]
The state or quality of being active; nimbleness; agility; vigorous action or operation; energy; active force; as, an increasing variety of human activities. "The activity of toil." Palfrey.
Syn. -- Liveliness; briskness; quickness.
Shades of meaning
Fernald has no entry of its own for activity; he lists it under exercise.
He lists it without comment; the entries above explain its neighbors.