1. the flawless system of basketball, created by Golden State Warriors coach Don Nelson, which often uses smaller players, three pointers, and speed to create havoc and pretty much own. Basically, the object is to cause offensive and defensive chaos, and use superior athleticism to win. There are really no major flaws either.
2. a positive adjective
1.
Person 1: "Wow, even though the Warriors are playing 5 shooting guards, they still won cause they had hella steals and 3's"

Person 2: Nellllllieball!!!

2. Person 1: "Wow that play was incredibly good!"
Person 2: "Yeah, that was sooo Nellieball"
by Monta June 20, 2008
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