Around 1940 and after, "a boner" was a screw up or mistake. So, to "pull a boner" was to make a mistake. Don't say "I pulled a boner" to your Teacher or Boss or police. they'll punnish you for that. If you're brave, you could try it with anyone else.
Wife- why'd you eat my cake?? I was saving that!

husband- "sorry Dear. I pulled a boner."
by mr. stuart March 31, 2006
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