Definition

1. Adjective:
   • Having undergone a chemical reaction with oxygen, resulting in a loss of electrons or an increase in oxidation state. This often involves the combination of a substance with oxygen or the removal of hydrogen.
   • Having a coating or appearance resulting from exposure to air and moisture, such as a tarnished metal.

Usage

• The term "oxidised" is primarily used in scientific, technical, and industrial contexts to describe materials that have reacted with oxygen. It can describe both intentional processes (like anodizing) and natural, often undesirable, processes (like rusting).
• It is the British English spelling. The American English spelling is "oxidized".

Examples

• Scientific Context:
  • The copper pipe had oxidised, forming a green patina.
  • In this experiment, the metal is easily oxidised in the presence of air.
• General/Descriptive Context:
  • She found an old, oxidised coin in the garden.
  • The statue's oxidised surface gave it an ancient appearance.

Advanced Usage

• "to become oxidised": to undergo the process of oxidation.
  • If iron becomes oxidised, it forms rust.
• "highly oxidised": describing a substance that has undergone a significant degree of oxidation.
  • Carbon dioxide is a highly oxidised form of carbon.

Variants and Related Words

• Oxidise (verb, British English): To cause to undergo oxidation. (US: )
  • Silver will oxidise when exposed to sulfur compounds in the air.
• Oxidation (noun): The process or result of oxidising.
  • The oxidation of the metal was accelerated by the saltwater.
• Oxidising agent (noun): A substance that causes oxidation by accepting electrons.
  • Chlorine is a powerful oxidising agent.

Synonyms

• Rusted (specifically for iron/steel)
• Tarnished (specifically for metals like silver)
• Corroded
• Weathered (more general, due to environmental exposure)

Antonyms

• Reduced (having gained electrons or undergone a chemical reduction)
• Unoxidised / Unoxidized
• Pure (in a metallic context, e.g., pure, untarnished metal)

Related Phrases

• Oxidised state: The condition of an element or compound after oxidation.
  • Iron in its oxidised state (as Fe³⁺) is common in rust.
• Prevent from oxidising: To stop the oxidation process.
  • A coat of paint can prevent steel from oxidising.

Adjective

1. combined with or having undergone a chemical reaction with oxygen
   • the oxidized form of iodine