In this case, "Level Wind" means nothing more than a Seaguar-specific marketing term to explain a special technique they use in putting the line on the spool.
From the Seaguar website:
10. What is Level Wind Technology and why does it make a difference?
Only Seaguar has Level Wind Technology in the fluorocarbon market. Level Wind Technology helps: Maintain Strength, Keep line Smoother, and Increase Cast-ability.
Also on the Seaguar website, they describe their Level Wind Technology process:
"...Level Wind Technology™, a Seaguar® exclusive. This process spools the line by laying it down side by side, never crossing itself. The final spool is as smooth as a spool of thread, with no cross contact marks, for maximum line strength without any line overstress or twist."
Oak Ridge Marina
2919 W. State Highway 154
Quitman, TX 75783