What's a cyclone and how does it differ from a hurricane or tornado?

Question

I am hearing all over about a cyclone in Oman. It's terrible.

But I am confused. I thought the words "cyclone" and "tornado" were interchangeable. But this looks like a hurricane.

Wow! So many GREAT answers ! Thanks to you all!!! :)

Answer 1

Cyclone model
http://www.srh.noaa.gov/srh/jetstream/synoptic/cyclone.htm

Tropical Cylone ( What is currently happening in Oman.)
http://www.srh.noaa.gov/srh/jetstream/tropics/tc.htm

Mesocyclone (MESO)
A storm-scale region of rotation, typically around 2-6 miles in diameter and often found in the right rear flank of a supercell (or often on the eastern, or front, flank of an HP storm). The circulation of a mesocyclone covers an area much larger than the tornado that may develop within it. Properly used, mesocyclone is a radar term; it is defined as a rotation signature appearing on Doppler radar that meets specific criteria for magnitude, vertical depth, and duration. It will appear as a yellow solid circle on the Doppler velocity products. Therefore, a mesocyclone should not be considered a visually-observable phenomenon (although visual evidence of rotation, such as curved inflow bands, may imply the presence of a mesocyclone).

Tornado (+FC)
A violently rotating column of air in contact with the ground and extending from the base of a thunderstorm. A condensation funnel does not need to reach to the ground for a tornado to be present; a debris cloud beneath a thunderstorm is all that is needed to confirm the presence of a tornado, even in the total absence of a condensation funnel. It nearly always starts as a funnel cloud and may be accompanied by a loud roaring noise. Tornadoes are classified by the amount of damage that they cause.

Answer 2

In the US cyclone and tornado are interchangeable, In the eastern part of the world cyclone is the same as a hurricane.

Answer 3

No, a cyclone, hurricane, and typhoon are all the same thing. The names follow local custom.

It is called a hurricane in the Atlantic or West Pacific near the Americas, a Typhoon if in the East Pacific near Asia, and a Cyclone in the Indian ocean.

Answer 4

Adding to the first answer(which was correct!!)

A tornado is a very violent, destructive kind of cyclone.
As you probably know, it occurs on land and is characterized by a funnel cloud.

In the past, people called all tornadoes "cyclones" (maybe that's why you were confused!)

Hope this helps!