investigational

adjective

in·​ves·​ti·​ga·​tion·​al in-ˌve-stə-ˈgā-sh(ə-)nəl How to pronounce investigational (audio)
1
: of or relating to investigation
investigational activities
2
: relating to or being a drug or medical procedure that is not approved for general use but is under investigation in clinical trials regarding its safety and efficacy
an investigational new drug

Examples of investigational in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Neuralink’s brain implants remain investigational and have not received approval from the US Food and Drug Administration or other regulatory authorities. — Neetika Walter, Interesting Engineering, 29 Oct. 2026 The study examined whether retatrutide, an investigational weight-loss drug from Eli Lilly, could help treat OSA in adults who were overweight or obese. — Angelica Stabile, FOXNews.com, 28 Oct. 2026 Eli Lilly on Wednesday said that its investigational drug was more effective at lowering blood sugar and cutting weight than Novo Nordisk’s Ozempic in a large diabetes study, further boosting the competitive profile of its medicine. — Elaine Chen, STAT, 28 Oct. 2026 The release of clinical trial data for felzartamab, an investigational treatment for rare kidney diseases, could also lift shares of Biogen considerably, per JPMorgan. — Liz Napolitano, CNBC, 12 Oct. 2026 See All Example Sentences for investigational

Word History

First Known Use

1905, in the meaning defined at sense 1

Time Traveler
The first known use of investigational was in 1905

Rhymes for investigational

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Browse Nearby Words

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investigational
investigative
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Cite this Entry

“Investigational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/investigational. Accessed 1 Nov. 2026.

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