Ok, I know willy willy's (known as whirl-winds in the states) are tiny, only about a few meters wide to perhaps a football field (at the most).
Cyclone is a general name for any low pressure center that spins counter clockwise. Like any wind that spins, will be a cyclone (hence the cyc, meaning circular)
Hurricanes occur over bodies of water, whereas tornadoes occur over land...
Typhoons are basically hurricanes, but in different areas. Typhoons/Hurricanes are generally much bigger than Tornadoes.
That's what I'd figured, but I checked a few places and they basically say the same thing. Some people complain that they're all the same thing, but I think they're full of it.
"I'm for it so we can put Nuclear power plants up there, and then beam the power back to earth on a laser beam." ~ Whidden