noun. A mixture of butter and suger. A mixture of butter and suger. The definition of a mixture is a combination of different things, or the state or act of being mixed. 1  An example of a mixture is a bowl of butter, sugar and salt. 2  An example of mixture is the process of combining flour and baking soda.
deuterium oxide. An isotope of water in which hydrogen has been displaced by its isotope deuterium. Its properties differ from ordinary water in that it has higher freezing and boiling points and is incapable of supporting life.
Deuterium and tritium are two isotopes of hydrogen, which is the only connection with the word âhydrogenâ: deuterium has one neutron, and tritium has two neutrons, while hydrogen atoms such as those in ordinary hydrogen gas have no neutrons, and could not be used to sustain a fusion reaction..