capsid

noun

cap·​sid ˈkap-səd How to pronounce capsid (audio)
: the protein shell of a virus particle surrounding its nucleic acid

Examples of capsid 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.
Many other viruses have their own capsid proteins, which form a shell around their genetic material, so this drug’s triumph raises the exciting prospect that similar capsid inhibitors could fight other viral diseases. — science.org, 12 Dec. 2024 Once inside the host cell, the capsid is shed, and the virus begins copying itself. — New Atlas, 15 July 2024

Word History

Etymology

French capside, from Latin capsa case + French -ide -id entry 2

First Known Use

1959, in the meaning defined above

Time Traveler
The first known use of capsid was in 1959

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“Capsid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/capsid. Accessed 11 Mar. 2025.

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Medical Definition

capsid

noun
cap·​sid ˈkap-səd How to pronounce capsid (audio)
: the protein shell of a virus particle that surrounds its nucleic acid
capsidal
-səd-ᵊl How to pronounce capsid (audio)
adjective
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