When you order fries at Burger King and you get an onion ring in with your order. Also works in reverse.

They are easiest to get when they are busy.
Dude! I got a double BK Bonus in my small fries today! That King is one creepy dude, but I love when that happens! BK Bonus FTW!
by superslacker87 May 18, 2009
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The random onion ring sometimes included in your order of BK french fries. It's kinda cool and kinda repulsive at the same time. Apparently, two completely separate receptacles for the fried side items is too lofty a concept for the King.
Chris: "Check it out! I got a BK bonus ring in my fries when we went through the drive thru!"

Smitty: "Look! I got a BK bonus fry in my onion rings!"

James: "BK sucks. Let's go to Chipotle."
by whiteboyDJ March 10, 2010
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