superoxide dismutase
noun
superoxide dis·mut·ase -dis-ˈmyü-ˌtās 
-ˌtāz
: a metal-containing antioxidant enzyme that reduces harmful free radicals of oxygen formed during normal metabolic cell processes to oxygen and hydrogen peroxide
Example Sentences
Recent Examples on the Web Dogs with two copies of a mutation in the gene superoxide dismutase 1 (SOD1) are at risk for the disease, but not all dogs with the mutation will develop the disease. 
Kim Campbell Thornton, sacbee, 10 Jan. 2018
Kim Campbell Thornton, sacbee, 10 Jan. 2018 Word History
Etymology
dismutation (simultaneous oxidation and reduction) + -ase
First Known Use
1969, in the meaning defined above
Medical Definition
superoxide dismutase
noun
superoxide dis·mu·tase -ˈdis-myü-ˌtās
: a metal-containing antioxidant enzyme that reduces potentially harmful free radicals of oxygen formed during normal metabolic cell processes to oxygen and hydrogen peroxide —abbreviation SOD