Skip to main content
inefficacious

inefficacious

9.4
Not effective at making the result you want
  • adjective
  • /ˌɪnɪˈfɪkəʃəs/
translation icon : ineficaz
  • Gorham argued that Senate appointments would be inefficacious because Senators would be partial to nominees hailing from their own home states; the President, on the other hand, would be careful to look through all the states for proper characters in making appointments.
  • inefficacious drug

Examples

  • That said, we should not assume that patients appeal to God's will only because a treatment has been deemed inefficacious or inaccessible.

    Academic text (2009)
  • However, an inefficacious drug can now be promoted, and its sales are increased as a result.

    Academic text (2016)
  • Saffron of Mars proved inefficacious.

    Fiction book (1991)
  • However, companies are now permitted to promote inefficacious drugs, leading presumably to increased sales without commensurate health effects.

    Academic text (2016)
  • This proved inefficacious.

    Fiction book (1990)
  • Grace "sweeps on to nature's perfection, a perfection beyond its intrinsic possibilities but not beyond its inefficacious desire."

    Academic text (2001)
  • For example, artificial insemination with donor sperm is rejected as a treatment for male infertility, but not because it is seen as inefficacious or inaccessible.

    Academic text (2009)
  • Analogically, not all examples of the power and creativity of humans in the form of free expression were useful; those retarding the formation of rational policies of governance were inefficacious.

    Academic text (1996)
  • So inefficacious were these methods that of the "fifteen decisive battles of the world" described by the Victorian historian Edward Creasy, intelligence drove the outcome of only one: Rome's victory over Carthage at the Metaurus River in 207 BC.

    Academic text (2006)
  • The teacher found her lectures to be inefficacious since none of the students improved their grades.

Synonyms

ineffective
vsinefficacious
90 3.4

Not working well enough to give the wanted result

is more formal and stresses lack of efficacy
inefficient
vsinefficacious
58 3.5

Not using time, work, or money well

is about failing to produce the intended result rather than poor resource use
unproductive
vsinefficacious
21 3.8

Not giving useful or wanted results

is about not achieving a specific intended effect rather than general usefulness
ineffectual
vsinefficacious
18 6.8

Not able to produce the result wanted

is about not producing results generally rather than lacking power
nonproductive
vsinefficacious
2 4.5

Not giving useful results or helping to finish work, like a meeting

is about failing to produce an intended effect rather than missing production contribution

Antonyms

986 3.1

Produces the intended result, for example a speech or medicine

efficacious
  • Formal
7 8.6

Able to produce the desired result

How Effective

successful
1.6
effective
986 3.1
inefficacious
9.4
useless
550 1.0

Surface Forms

inefficacious positive

Morphology

inefficacious = efficacious (semi-transparent) = in + efficac + ious

If a learner knows 'efficacious', adding the negative prefix 'in-' straightforwardly gives the meaning 'not efficacious'.

Etymology

Inefficacious starts with in- meaning 'not' and the rest comes from a root meaning 'to produce', the same idea you see in effect. So inefficacious means 'not' able to 'produce' the result you want.