High power rockets can be classified a few different ways: sport, scale, and oddrocs (and others depending on the kit suppliers).
Sport are usually basic 3FNC or 4FNC rockets.
Scale looks like actual rockets or missiles (Phoenix, AMRAAM, Honest John, Nike Smoke, Saturn V)
Oddrocs are spools, pyramids, saucers. Things that don't look much like rockets but still fly on a rocket motor.
Off the top of my head, Public Missiles Limited (PML)'s website would be a good place to look. Their rocket kits are categorized into sport and scale. Madcow also lets you sort by type of rocket, and sport and scale are a couple of the categories.
I think it is well worth slicing that general definition into the multiple narrower categories that have been mentioned in the thread.Gee's!
All of our LPR, MPR & HPR rockets that are NOT flown in Sanctioned competition regardless of sub-type (ie: Scale, Odd-Roc, PMC, BG, RG or Helicopter) are by their very existance Sport Flying Rockets. or Sport Rocketry.
While we use many of the same methods, formulas, and math the professionals use...they ARE NOT professional rockets - We Are Non-Professional HOBBIEST.
I don't think there is a clear definition for "Sport Rocket".What is a "sport" rocket (as opposed to a model rocket which is not a sport rocket)?
As others have noted, "sport" is also used to differentiate non-contest from contest rocketry as in the National "Sport" Launch versus NARAM.We use the phrase "Sport Rocketry" to describe our hobby and "Sport" as a default category for rockets that don't fall into one of the other categories by style (such as "Odd Rocket," "Scale," etc.)
Originally, I would guess, our rockets were divided into just "Scale" and "Sport" (non-scale) before other styles were added.
Both uses are based on the somewhat archaic use of "sport" as a synonym for "recreation."