http://www.leg.state.fl.us/statutes...TM&Title=->2009->Ch0790->Section 001#0790.001
3)(a) "Concealed weapon" means any dirk, metallic knuckles, slungshot, billie, tear gas gun, chemical weapon or device, or other deadly weapon carried on or about a person in such a manner as to conceal the weapon from the ordinary sight of another person.
13) "Weapon" means any dirk, knife, metallic knuckles, slungshot, billie, tear gas gun, chemical weapon or device, or other deadly weapon except a firearm or a common pocketknife, plastic knife, or blunt-bladed table knife.
The wording has changed a little bit to include knife under "Weapon". Also, the common pocketknife wording doesn't appear in "concealed weapon"
http://www.thefiringline.com/library/blades/knifelaws.html
The phrase "common pocketknife" is really open to interpretation (depends on the cop or the jury), and there has been one ruling/case where a tactical knife was ruled not a common pocket knife. J.D.L.R. v State 701 So. 2d 626 (1997).
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Ok did some more research, apparently there was a ruling by the Florida Supreme Court in 1997 (L.B. v. State, 700 So. 2d 370, 373) that interpreted the phrase "common pocketknife" as a knife with a blade shorter than 4 inches.
So a concealed weapon is any deadly device, including a knife.
But a weapon (non concealed) can be a benchmade infidel with a 3.95 inch blade.