Mixed-oxide nuclear fuel; made from uranium and plutonium

Mixed Oxide Fuel (a mixture of plutonium oxide and uranium oxides).

Mixed oxide fuel - a mixture of plutonium and uranium dioxides, with up to ~7% total plutonium (~5% of fissile plutonium) in the heavy metal, typically for use in light water reactors

In the Time Splitters video game series the Mox are an alien species that inhabit Planet X and are divided into races which seem to be forever at war. They are a humanoid species with heads similar to that of an octopus. Their skin has been observed to be a variety of colors.

Mox, the JavaScript library of choice.