inefficacious

American  

[in-ef-i-key-shuhs] / ˌɪn ɛf ɪˈkeɪ ʃəs /

adjective

1. not able to produce the desired effect; ineffective.

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inefficacious British  

/ ˌɪnɛfɪˈkæsɪtɪ, ˌɪnɛfɪˈkeɪʃəs, ɪnˈɛfɪkəsɪ /

adjective

1. failing to produce the desired effect

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Other Word Forms

• inefficaciously adverb
• inefficaciousness noun
• inefficacity noun
• inefficacy noun

Etymology

Origin of inefficacious

First recorded in 1650–60; in- ³ + efficacious

Example Sentences

Remedies for the starling plague were suggested, some facetious, some earnest, all equally inefficacious.

From Time Magazine Archive

Most nostrums hit at only one of the causes and so are frequently inefficacious.

From Time Magazine Archive

Every argument was brought forward to induce him to stay in La Rochelle, but every argument proved inefficacious.

From The Huguenot: (Volumes I-III) A Tale of the French Protestants. by James, G. P. R. (George Payne Rainsford)

The ordinary remedies—such as salt dissolved in water—are inefficacious.

From Sheep, Swine, and Poultry Embracing the History and Varieties of Each; The Best Modes of Breeding; Their Feeding and Management; Together with etc. by Jennings, Robert

It is said, that though, to satisfy the Scotch Commissioners, all their requests were ostensibly granted, Henry took secret measures to render these grants entirely inefficacious.

From Life of Mary Queen of Scots, Volume I (of 2) by Bell, Henry Glassford