inefficacious

[ in-ef-i-key-shuhs ]

adjective

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

inefficacious

/ ˌɪnɛfɪˈkeɪʃəs; ˌɪnɛfɪˈkæsɪtɪ; ɪnˈɛfɪkəsɪ /

adjective

1. failing to produce the desired effect

Derived Forms

• ˌineffiˈcaciously, adverb
• inefficacy, noun

Other Words From

• inef·fi·cacious·ly adverb
• inef·fi·cacious·ness in·ef·fi·cac·i·ty [in-ef-i-, kas, -i-tee], noun

Word History and Origins

Origin of inefficacious¹

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

Example Sentences

All attempts at cure proving inefficacious, he had at length to settle down once more in London.

From Project Gutenberg

The next was in 1641, when Charles I. returned from his imprudent and inefficacious journey into Scotland.

From Project Gutenberg

I therefore once more directed squill, with decoction of seneka and sal sodæ; but it was inefficacious.

From Project Gutenberg

The trials were made only on small animals, but in each case the alleged remedy proved inefficacious.

From Project Gutenberg

Their united efforts were vain, however; and even the remedies suggested by Apollo, god of medicine, proved inefficacious.

From Project Gutenberg