The spelling of the word "made boner" may seem unusual, but it is actually a phonetic rendering of the phrase "made a mistake." The IPA phonetic transcription for "mistake" is /mɪˈsteɪk/, and when spoken quickly or in a colloquial context, it is possible for the two words to blend together and be pronounced as "madeboner." However, this spelling should not be used in formal writing or speech as it can be seen as vulgar and offensive.