at·​ten·​u·​at·​ed | \ ə-ˈten-yə-ˌwā-təd How to pronounce attenuated (audio) , -yü-ˌā-təd \

Definition of attenuated

1 : lessened or weakened (as in amount, force, or magnitude) "It wasn't that there was less effect, or an attenuated effect. There was no effect at all."— Roger Simon … people who are not, even in Facebook's attenuated sense of the word, your "friends" …— Robert Wright But I am aware that my connection to Russia is an attenuated connection. I do not know Russian or Russia as well as my parents did.— Keith Gessen The attenuated [radio] signals from Phoenix and LA were too scratchy to enjoy.— A. E. Maxwell
2 medical : being or containing a pathogenic agent that has been altered to be of greatly reduced virulence Measles vaccines are just that, weakened (or attenuated) measles viruses.— Ann Finkbeiner et al. Influenza viruses for both the inactivated and live attenuated influenza vaccines are initially grown in embryonated hens' eggs.Centers for Disease Control and Prevention
3 : long and slender from or as if from having been stretched Glass artist Lino Tagliapietra, who is widely known for his elegant, attenuated glass vessels …— Steven Litt … the glamorous women … appear impossibly graceful with their attenuated figures, long necks, and slender arms.— Stephanie L. Herdrich

Did You Know?

A friendship can become attenuated if neither person bothers to keep in touch. Radio waves can become attenuated by the shape of the landscape, by foliage, by atmospheric conditions, and simply by distance. Factory workers and rock musicians often use noise-attenuating ear plugs to save their hearing. To attenuate something isn't to stop it, just to tone it down.

First Known Use of attenuated

1798, in the meaning defined at sense 1

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The first known use of attenuated was in 1798

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Cite this Entry

“Attenuated.” Dictionary, Merriam-Webster, Accessed 5 Jul. 2020.

More from Merriam-Webster on attenuated

Thesaurus: All synonyms and antonyms for attenuated

Britannica English: Translation of attenuated for Arabic Speakers

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