I've never really thought about it. On the few times I've talked of ... the twister things ... the names of hurricane and tornado have been used interchangeably.
Here's the definitions according to dictionary.com:
Hurricane - 1. a violent, tropical, cyclonic storm of the western North Atlantic, having wind speeds of or in excess of 72 miles per hour (32 m/sec). Compare tropical cyclone, typhoon.
2. a storm of the most intense severity.
3. anything suggesting a violent storm.
Tornado - 1. a localized, violently destructive windstorm occurring over land, especially in the Middle West, and characterized by a long, funnel-shaped cloud extending toward the ground and made visible by condensation and debris. Compare waterspout ( def. 3 ) .
2. a violent squall or whirlwind of small extent, as one of those occurring during the summer on the west coast of Africa.
3. a violent outburst, as of emotion or activity.
That about right?
I am a Star Wars fan. That doesn't mean that I hate or love Jar Jar. That doesn't mean I hate or love Lucas, or agree or disagree 100% with him. That doesn't mean I prefer the PT over the OT, or vice versa. That doesn't mean I hate the EU, or even love all of it (or even read all of it). These are not prerequisites. Being a man is not a prerequisite. Being a geek is not a prerequisite. The only prerequisite is that I love something about Star Wars. I am a Star Wars fan.