When you have a random erection for no apparent reason, therefore nothing in the vicinity can claim your boner. Often appears at the most unfortunate and awkward of times.
Oisin: My job interview to become a pre school teacher didn't go so well, and my no claims boner didn't help either!

Jordon: I hope no one at the family reunion saw my no claims boner...

Shane: Thankfully, after ten minutes my grandmother came in to the room and broke my no claims boner
by Daneeyul January 26, 2014
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