non·​struc·​tur·​al ˌnän-ˈstrək-chə-rəl How to pronounce nonstructural (audio)
: not part of a structure : not relating to, affecting, or contributing to the structure of something
free-standing panels and other nonstructural elements
nonstructural movable parts
of a viral protein : expressed in an infected cell but not incorporated into the virion particle
nonstructural proteins

Example Sentences

Recent Examples on the Web There are two major categories of viral proteins: structural and nonstructural. William A. Haseltine, Forbes, 2 May 2022 But while structured exercise is crucial, daily nonstructural movement is also key to living a long and healthy life. Sara Novak, Discover Magazine, 7 Apr. 2022 Here, the nonstructural proteins help with viral replication by regulating transcription and impairing host defenses. William A. Haseltine, Forbes, 2 May 2022 In October 2020, researchers discovered that the SARS-CoV-2 nonstructural protein 5 (NSP5), like many other of its viral proteins, suppresses innate immunity. William A. Haseltine, Forbes, 19 Jan. 2022 As the main protease, NSP5 drives the enzymatic processes necessary for the virus to reproduce itself, chewing up chunkier polyproteins into discrete nonstructural proteins that assist in the virus’ program of immune suppression. William A. Haseltine, Forbes, 19 Jan. 2022 The other is an endonuclease, nonstructural protein 15 (NSP15). William A. Haseltine, Forbes, 28 Oct. 2021 According to a study published in April 2020, mutations identified in the nonstructural protein NSP6 and open reading frame Orf10 likely prevent autophagosomes from delivering material to the lysosome. William A. Haseltine, Forbes, 7 Sep. 2021 This leaves mutations in nonstructural proteins, 3’ structural proteins, and 3’ regulatory (accessory) proteins relatively uninvestigated, despite playing a significant role in host immune suppression and pathogenesis. William A. Haseltine, Forbes, 3 Sep. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nonstructural.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1879, in the meaning defined at sense 1

Time Traveler
The first known use of nonstructural was in 1879

Dictionary Entries Near nonstructural

Cite this Entry

“Nonstructural.” Dictionary, Merriam-Webster, Accessed 31 Jan. 2023.

Last Updated: - Updated example sentences
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