In*ef`fi*ca"cious (?), a. [Pref. in-
not + efficacious: cf. F. inefficace, L.
inefficax.] Not efficacious; not having power to produce
the effect desired; inadequate; incompetent; inefficient;
impotent. Boyle.
The authority of Parliament must become
inefficacious . . . to restrain the growth of
disorders.
Burke.
&fist; Ineffectual, says Johnson, rather denotes an actual
failure, and inefficacious an habitual impotence to any
effect. But the distinction is not always observed, nor can it be;
for we can not always know whether means are inefficacious
till experiment has proved them ineffectual.
Inefficacious is therefore sometimes synonymous with
ineffectual.
