1. A team in any sport, that comes into the playoffs as an underdog, and sweeps a contending team. Upset underdog

2. A team in nba2k who destroys your team after you've been on a huge win streak.
Example: "See fam, it's all fun and games until you run into the knock-off boyz"

Example: "Bruh, don't sleep on these dudes, they probably the knock-off boyz"
Example: "those 2011 Dallas mavericks were the knock-off boys.
by Jay XLA Black December 21, 2016
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