Invalid and Inefficacious

Invalid

Invalid adjective - Chronically or repeatedly suffering from poor health.

Inefficacious and invalid are semantically related. In some cases you can use "Inefficacious" instead an adjective "Invalid".

Inefficacious

Inefficacious adjective - Not producing the desired result.

Invalid and inefficacious are semantically related. Sometimes you can use "Invalid" instead an adjective "Inefficacious".
Cite this Source
Inefficacious and Invalid. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/invalid/inefficacious
Invalid & Inefficacious. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/invalid/inefficacious>.
Inefficacious or Invalid. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/invalid/inefficacious.
Google Ngram Viewer shows how "invalid" and "inefficacious" have occurred on timeline