As my teacher told us, oxidation is the gaining of oxygen and reduction is the donation of oxygen. In my reference book there are other definitions of this reaction.
So please give me some alternate definitions and, if possible, explain it.
redox reaction: The reaction in which oxidation and reduction occurs simentationesly is called redox reaction
There are mainly three different ways of determining oxidation and reduction reaction.
Addition of oxygen or removal of hydrogen is called oxidation. Addition of hydrogen and removal of oxygen is called reduction.
Electron transfer method [method which you mentioned.]
Oxidation State method [Highly used]
Increase in oxidation state is called oxidation. Decrease in oxidation state is called reduction.
redox reaction: The change in oxidation state of reactant occure in reaction is called redox reaction.
You might learn Oxidation State method in your higher class.