"In chemistry, oxidizing agent has two meanings. In one sense, an oxidizing agent is a chemical species that removes an electron from another species...In the second sense, an oxidizing agent or an oxidizer is a chemical species that transfers electronegative atoms... to a substrate."

"Electron acceptors participate in electron-transfer reactions.
In this context, the oxidizing agent is called an electron acceptor and the reducing agent is called an electron donor."

"Of great interest to chemists are the details of the electron transfer event,
which can be described as inner sphere or outer sphere."

https://en.wikipedia.org/wiki/Oxidizing_agent