Iron oxide is not a transition metal. It is a compound formed from the transition metal iron (Fe) and oxygen (O).

Here's why:

* Transition metals are elements that have partially filled d orbitals in their atoms.

* Iron oxide (FeO, Fe₂O₃, Fe₃O₄) is formed by the chemical reaction between iron and oxygen. It is an ionic compound where iron has lost electrons and oxygen has gained electrons.

Therefore, while iron oxide contains a transition metal, it is not itself a transition metal. It is a compound made from a transition metal.