cofactor
noun
co·fac·tor
ˈkō-ˌfak-tər 
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
Aiding collagen production: Vitamin C is an important cofactor, or partner, for the enzymes that build collagen, the skin’s primary building block.
—
Adam Hurly, Robb Report, 29 July 2025
The scientists put enzymes and helper molecules that aid in chemical reactions, called cofactors, on to these electrodes.
—New Atlas, 28 Mar. 2025
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
Zinc also has a synergistic relationship with vitamin D, acting as a cofactor for vitamin D functions and aids vitamin D to work inside human cells.
—Amiah Taylor, Discover Magazine, 25 Dec. 2024
In addition to its effects on DNA, magnesium has been identified as a cofactor in over 300 enzyme systems in the body, including those that regulate blood pressure, control blood glucose levels, and ensure proper nerve function.
—Killian Baarlaer, The Courier-Journal, 19 Dec. 2024
Dean cites scientific research that has found 80% of metabolic functions involve magnesium as a cofactor, including facilitating fat metabolism, controlling blood pressure, and normalizing hormone secretion.
—Kyle MacNeill, Vogue, 14 June 2024
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Adam Hurly, Robb Report, 29 July 2025
The scientists put enzymes and helper molecules that aid in chemical reactions, called cofactors, on to these electrodes.
—New Atlas, 28 Mar. 2025
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
Zinc also has a synergistic relationship with vitamin D, acting as a cofactor for vitamin D functions and aids vitamin D to work inside human cells.
—Amiah Taylor, Discover Magazine, 25 Dec. 2024
In addition to its effects on DNA, magnesium has been identified as a cofactor in over 300 enzyme systems in the body, including those that regulate blood pressure, control blood glucose levels, and ensure proper nerve function.
—Killian Baarlaer, The Courier-Journal, 19 Dec. 2024
Dean cites scientific research that has found 80% of metabolic functions involve magnesium as a cofactor, including facilitating fat metabolism, controlling blood pressure, and normalizing hormone secretion.
—Kyle MacNeill, Vogue, 14 June 2024
Cite this Entry
“Cofactor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cofactor. Accessed 31 Oct. 2025.
Copy CitationMedical Definition
cofactor
noun
co·fac·tor
ˈkō-ˌfak-tər
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
Elissa Mendenhall, MotheringLove words? Need even more definitions?
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