oxidize

verb

ox·​i·​dize ˈäk-sə-ˌdīz 

oxidized; oxidizing

transitive verb

1

: to combine with oxygen

Other chemicals then oxidize the sulfur dioxide to form sulfuric acid, which along with the nitric acid increases the acidity of the dewdrop.

—R. Monastersky

Should the cork be allowed to dry out, it will shrink and allow air to seep in and oxidize the wine.

—Peter D. Meltzer

2

: to dehydrogenate especially by the action of oxygen

oxidize an alcohol to an aldehyde

3

: to change (a compound) by increasing the proportion of the electronegative part or change (an element or ion) from a lower to a higher positive valence

What mix of products is formed is a function of the electrode potential used to oxidize the chloride ion.

—Chemical & Engineering News

: remove one or more electrons from (an atom, ion, or molecule)

oxidize metallic copper to ionic copper

intransitive verb

: to become oxidized

Fats can either oxidize (combine with oxygen) or hydrolyze (combine with water) to become rancid.

—Shirley Corriher

Silver does not oxidize, or rust, on exposure to air. In fact, compared with most other elements, it is not particularly reactive.

—C. Claiborne Ray

oxidizable

ˌäk-sə-ˈdī-zə-bəl 

adjective

Examples of oxidize in a Sentence

The paint oxidizes and discolors rapidly.

Recent Examples on the Web

The techniques for making green, black, oolong, or white tea vary according to the length of time the leaves — which should be young when harvested — are oxidized or air-exposed following harvest; the more time spent on oxidation, the darker the tea. —Joshua Siskin, Oc Register, 8 Aug. 2025

However, when copper levels are too high and the water isn't properly balanced, the metal can oxidize and bind to light-colored fur—resulting in a greenish tint. —Alice Gibbs, MSNBC Newsweek, 18 July 2025

Consider innovative delivery systems: Powdered Vitamin C serums are a great option, as being suspended in water can cause the ingredient to oxidize. —Adam Hurly, Robb Report, 29 July 2025

During processing, Oolong tea is partially oxidized (10% to 70%). —Sarah Bence, Verywell Health, 22 July 2025

Word History

First Known Use

1802, in the meaning defined at transitive sense 1

Phrases Containing oxidize

• re-oxidize

Rhymes for oxidize

• advertise
• aggrandize
• agonize
• alibis
• alkalies
• alkalis
• amortize
• amplifies
• analyse
• analyze
• anywise
• authorize

Kids Definition

oxidize

verb

ox·​i·​dize ˈäk-sə-ˌdīz 

oxidized; oxidizing

1

: to combine with oxygen

2

: to remove hydrogen from especially by the action of oxygen

3

: to remove one or more electrons from (an atom, ion, or molecule)

4

: to become oxidized

oxidizer noun

Medical Definition

oxidize

verb

ox·​i·​dize

variants also British oxidise

ˈäk-sə-ˌdīz 

oxidized also British oxidised; oxidizing also British oxidising

transitive verb

1

: to combine with oxygen

2

: to dehydrogenate especially by the action of oxygen

3

: to change (a compound) by increasing the proportion of the electronegative part or change (an element or ion) from a lower to a higher positive valence : remove one or more electrons from (an atom, ion, or molecule)

intransitive verb

: to become oxidized

oxidizable

-ˌdī-zə-bəl 

adjective