# oxidation

/ˌɑksəˈdeɪʃən/ (US) · /ˌɒksɪdˈeɪʃən/ (UK)

Source: https://englishreference.com/word/oxidation
Updated: 2026-08-08

## Senses

### 1. combining with oxygen

noun · CEFR C1 · Technical

the process of a substance joining with oxygen, which can cause things like metal to rust or fruit to turn brown.

For teachers: the chemical combination of a substance with oxygen. Often used in contexts describing corrosion or organic decay.

- The oxidation of the iron gate caused it to turn orange and crumble over time.
- Atmospheric oxidation is the primary cause of structural degradation in unprotected steel bridges exposed to coastal air.

Usage: Often functions as an uncountable noun when describing the general process.

### 2. loss of electrons

noun · CEFR C1 · Technical

a chemical reaction where an atom or molecule loses electrons.

For teachers: a reaction in which the atoms of an element lose electrons, resulting in an increase in the oxidation state.

- In this battery, oxidation happens at the negative side to create an electric current.
- The researcher monitored the oxidation of the zinc electrode to determine the efficiency of the electrochemical cell.

Usage: Frequently paired with 'reduction' in the portmanteau 'redox' to describe simultaneous electron transfer.

## Examples

- The rust on the old car is caused by oxidation.
- To prevent the oxidation of the sliced fruit, the chef dipped the pieces in lemon juice.
- In cellular respiration, the oxidation of glucose provides the necessary energy for various biological processes to sustain life within the organism.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.