A childhood belief about oral sex

I used to believe that oral sex meant that you talked to somebody while you were both masturbating. I had taken an oral exam shortly before hearing the term, and the teacher said "oral" meant "out loud," During the Clinton scandal, the term "oral sex" was all over my school, but nobody actually said what it meant, just that it wasn't "real" sex and it didn't count as cheating. My definition seemed to fit those criteria, so I convinced myself of it for about a year.