ineffective

adjective

in·​ef·​fec·​tive ˌi-nə-ˈfek-tiv 

1

: not producing an intended effect : ineffectual

ineffective lighting

2

: not capable of performing efficiently or as expected : incapable

an ineffective executive

ineffectively adverb

ineffectiveness noun

Synonyms

• unsuccessful
• inefficient
• counterproductive

Examples of ineffective in a Sentence

The treatment was ineffective against the disease.

an ineffective effort to reduce unemployment that only spurred inflation

Recent Examples on the Web

Most importantly, the vaccines that contain aluminum would be rendered ineffective. —NPR, 31 Oct. 2025

Welcome’s report sees that remedy as ineffective, and the collapse in split-ticket voting in recent elections suggests the group may be right. —David Weigel, semafor.com, 27 Oct. 2025

The ground game was completely ineffective in wins over the Bills and Saints in Weeks 5 and 6. —Doug Kyed, Boston Herald, 26 Oct. 2025

The lethal removal of a bear is ineffective, and people should be trained to properly lock away food, Fleishman said. —Ishani Desai, Sacbee.com, 25 Oct. 2025

Word History

First Known Use

1649, in the meaning defined at sense 1

Rhymes for ineffective

• intellective
• introspective
• irrespective
• nondirective
• nonselective
• retrospective
• unreflective
• advective
• affective
• collective
• connective
• convective

Kids Definition

ineffective

adjective

in·​ef·​fec·​tive ˌin-ə-ˈfek-tiv 

1

: not producing the desired effect

an ineffective law

2

: not performing as well as expected or needed

an ineffective leader

ineffectively adverb

ineffectiveness noun