Oh, great! You mean in Australia, cyclones are something else? Here in the States, people think there's a difference between tornadoes and cyclones. The only difference is depends on the dialect. That, basically, those from Texas and the area surrounding only use cyclone when they mean tornado. Now, technically, tornado is the incorrect word as, meteorlogically, cyclone is the correct term across the board. Even a hurricane is technically what is called a mesocyclone. But, here in the States, people, too, believe there is no difference between a tornado and a hurricane. A hurricane/typhoon is just a cyclone that occurs over water and is powered by the energies in them. So, basically, tornadoes are cyclones, by definition, and that hurricanes and typhoons are also cyclones, but the difference is they occur over water only and are technically to be called mesocyclones. If they occur in the air or on solid ground, they're just plain cyclones.
And, that's our daily lesson from Bill Nye, The Science Guy!