spike protein

noun

variants or less commonly spike glycoprotein

plural spike proteins also spike glycoproteins

: a glycoprotein that protrudes from the envelope of some viruses (such as a coronavirus) and facilitates entry of the virion into a host cell by binding to a receptor on the surface of a host cell followed by fusion of the viral and host cell membranes

Like a key in a lock, these spike proteins fuse to receptors on the surface of cells, allowing the virus's genetic code to invade the host cell, take over its machinery and replicate.

—Bruce Lieberman

Their results, published in Science, confirm that the spike protein on the virus that causes COVID-19 is quite similar to that of its close relative, the SARS virus.

—Francis Collins

Using a powerful imaging technique … , researchers from the National Institutes of Health, Weill Cornell Medical College and Yale University School of Medicine observed the motions of key proteins on the surface of HIV called spike proteins.

—Emily Mullin

called also S protein

Examples of spike protein in a Sentence

Recent Examples on the Web

This induces an immune system response to the spike protein that is present on the coronavirus. —Joshua P. Cohen, Forbes.com, 2 Sep. 2025

Once injected into the body, the vaccine releases the mRNA to program the cell to produce the spike proteins like those on the surface of SARS-CoV-2, the COVID-19 virus. —Melina Khan, USA Today, 7 Aug. 2025

That portion of the spike protein is considered an antigen. —Beth Mole, ArsTechnica, 7 Aug. 2025

The mRNA instructions from vaccination degrade within a few days, and studies suggest the spike protein generated by such vaccination against COVID lasts about a month in the body. —Stephanie Pappas, Scientific American, 6 Aug. 2025

Word History

First Known Use

1969, in the meaning defined above

Rhymes for spike protein

• acetylene
• adenosine
• amphetamine
• anthropocene
• antipyrine
• apomorphine
• apoprotein
• aquamarine
• arsphenamine
• azobenzene
• buprenorphine
• chlorobenzene

Medical Definition

spike protein

noun

variants also spike glycoprotein

: a glycoprotein that protrudes from the envelope of some viruses (as a coronavirus) and facilitates entry of the virion into a host cell by binding to a receptor on the surface of a host cell followed by fusion of the viral and host cell membranes

called also S protein