Queries about oxidation and reduction

Hello

I am having troubles with the correct usage of the terms "oxdised", "reduced", "oxidising agent", and "reducing agent". I understand the redox concept thoroughly, I would just like clarification on the usage of the words.

I think the problem will be best illustrated using an example. Say, the reaction between Fe2O3 and CO:

Fe2O3(s) + 3CO(g) --> 2Fe(l) + 3CO2(g)

Oxidation numbers are as follows:

Reactants:

Fe = +3

O = -2

C = +2

Products:

Fe = 0

C = +4

O = -2

Now here is the dilemma: Do I say "the Fe2O3 has been reduced, and has acted as the oxidising agent" or "the Fe has been reduced, and the Fe2O3 has acted as the oxidising agent", or a mixture of either. Is it the element that has been oxidised/reduced or the whole compound? Then, is it the whole compound or just the element that is the oxidising/reducing agent? Or does it depend on what the question is asking? Or does it even depend on whether it is ionic or covalent, because one ion may be oxidised/reduced independent of what has happened to the other.

Please help, this is driving me crazy. Hopefully I explained my issue well enough