cofactor

noun

co·​fac·​tor ˈkō-ˌfak-tər How to pronounce cofactor (audio)
1
: the signed minor of an element of a square matrix or of a determinant with the sign positive if the sum of the column number and row number of the element is even and with the sign negative if it is odd
2
: a substance that acts with another substance to bring about certain effects
especially : coenzyme
3
: something (such as diet or a virus) that acts with or aids another factor in causing disease

Examples of cofactor in a Sentence

Recent Examples on the Web
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For example, manganese is a cofactor for manganese superoxide dismutase, an antioxidant enzyme that protects cells from damage caused by reactive oxygen species (ROS).2 As a cofactor for various enzymes, manganese is involved in many essential aspects of health. — Jillian Kubala, Health, 5 Feb. 2025 Zinc is an important cofactor in the hair growth cycle. — Olivia Munson, USA TODAY, 7 Jan. 2025

Word History

First Known Use

1885, in the meaning defined at sense 1

Time Traveler
The first known use of cofactor was in 1885

Rhymes for cofactor

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“Cofactor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cofactor. Accessed 22 Mar. 2025.

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Medical Definition

cofactor

noun
co·​fac·​tor ˈkō-ˌfak-tər How to pronounce cofactor (audio)
1
: a substance that acts with another substance to bring about certain effects
especially : coenzyme
2
: something (as a diet or virus) that acts with or aids another factor in causing disease
Infection with the HPV virus is an important cofactor in cervical cancer, but very few people infected with HPV will ever get cervical cancer.— Elissa Mendenhall, Mothering

More from Merriam-Webster on cofactor

Britannica.com: Encyclopedia article about cofactor

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