boner (n.)youdaoicibaDictYouDict[boner 词源字典]
"blunder," 1912, baseball slang, probably from bonehead. Meaning "erect penis" is 1950s, from earlier bone-on (1940s), probably a variation (with connecting notion of "hardness") of hard-on (1893).[boner etymology, boner origin, 英语词源]