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

Given as a shot, mRNA enters muscle cells and teaches them to produce a spike protein found on the surface of a virus. —Stephanie Armour | Kff Health News, ABC News, 8 Mar. 2025

Bjorkman pulls out a model of the spike protein that is about the size of her head (in other words: very not to scale). —Maggie Chen, WIRED, 26 July 2022

The spike protein of the new coronavirus infected human cells that had high levels of the ACE2 receptor in test tubes, as well as in small models of human airways and intestines. —Youri Benadjaoud, ABC News, 24 Feb. 2025

In addition to the elevated spike proteins, other factors could increase the risk of post-vaccination syndrome. —Melissa Rudy, Fox News, 24 Feb. 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