Of course Brian and Swimbait nailed the definition.

One would have to be a lure historian to understand my definition: a swimbait is the modern soft plastic version of the old rubber French Viv Vif lure.

I acquired a Viv Vif years ago, used it once off the coast of New Jersey and caught Atlantic bluefish with it. In the classic movie "The Graduate" Mrs. Robinson's husband tells Dustin Hoffman's character to go into the plastics industry for a great future. I should have taken that advice and started making plastic Viv Vifs before anyone else.