When I was a kid, my teen-aged sister and her girlfriend would sing the chorus of "Woman, Woman" by Gary Puckett & the Union Gap as "woman, have you got Gene on your mind?" (Her friend was going out with this one guy but also liked a guy named Gene.) It was at least 20 years later that I finally realized the line was "woman, have you got cheating on your mind?" And even though it's been 20 years since that realization, I still sing it with "Gene" in the verse.
A childhood belief about misheard lyrics

others believed things like this
- My sister just recently realized that the lyric "more than a woman" wasn't 4 letter woman!— Anne
- I thought the line in the song "more than a woman" was "four-legged woman".— boo
- When i was about 3 or 4 i thought Gene Simmons was the Boogie Man.— miss13
- I used to think that the song "Evil Woman" was "Medieval Woman". Anon
- My Mom used to believe that there was a woman named Mrs. Sippy.— Linda
- I used to think I was Wonder Woman! Don't I wish it was so now!Anon