_doing_. _Act_ is therefore single, individual,
momentary; _action_ a complex of _acts_, or a process, state, or habit
of exerting power. We say a virtuous _act_, but rather a virtuous course
of _action_. We speak of the _action_ of an acid upon a metal, not of
its _act_. _Act_ is used, also, for the simple _exertion_ of power; as,
an _act_ of will. In this sense an _act_ does not necessarily imply an
external _effect_, while an _action_ does. Morally, the _act_ of murder
is in the determination to kill; legally, the _act_ is not complete
without the striking of the fatal blow. _Act_ and _deed_ are both used
for the thing done, but _act_ refers to the power put forth, _deed_ to
the result accomplished; as, a voluntary _act_, a bad _deed_. In
connection with other words _act_ is more usually qualified by the use
of another noun, _action_ by an adjective preceding; we may say a kind
_act_, though oftener an _act_ of kindness, but only a kind _action_,
not an _action_ of kindness. As between _act_ and _deed_, _deed_ is
commonly used of great, notable, and impressive _acts_, as are
_achievement_, _exploit_, and _feat_.

_Festus_: We live in _deeds_, not years; in thoughts, not breaths.

BAILEY _Festus, A Country Town_, sc. 7.

A _feat_ exhibits strength, skill, personal power, whether mental or
physical, especially the latter; as, a _feat_ of arms, a _feat_ of
memory. An _exploit_ is a conspicuous or glorious _deed_, involving
valor or heroism, usually combined with strength, skill, loftiness of
thought, and readiness of resource; an _achievement_ is the doing of
something great and noteworthy; an _exploit_ is brilliant, but its
effect may be transient; an _achievement_ is solid, and its effect
enduring. _Act_ and _action_ are both in contrast to all that is merely
passive and receptive. The intensest _action_ is easier than passive
endurance.

Antonyms:

cessation, immobility, inertia, quiet, suffering,
deliberation, inaction, passion,[A] repose, suspension.
endurance, inactivity, quiescence, rest,

[A] In philosophic sense.

* * * * *

ACTIVE.

Synonyms:

agile, energetic, officious, sprightly,
alert, expeditious, prompt, spry,
brisk, industrious, quick, supple,
bustling, lively, ready, vigorous,
busy, mobile, restless, wide awake.
diligent, nimble,

_A