Used as a compliment to a courageous person or as an expression to explain that someone has a lot of courage aka balls.

Similar to - that person has huge balls or they have big balls. One could say that - they have balls to spare.

Hope that makes sense :)
The people who rock climb without ropes (free solo climbing) have balls to spare.

Anyone going up against an oppressive government has balls to spare.
by Happysun September 7, 2016
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