A friend of mine has a grand daughter named Madison. When she was born, I said - "Madison? Like in Splash?" and she looked at me like I was from Mars. First of all I don't think she had ever heard of or seen one of my all time favorite movies "Splash". Secondly (after I told her about it), I think she was a bit offended that I thought her daughter was named after a fictional mermaid. But she was... rather they realized it or not.
Splash came out in 1984 and I think the weekend it was released, my friend Susan and I made a bee-line for the theater because we loved Tom Hanks (from Bosom Buddies). We loved John Candy (from SCTV) and thought it looked like a really cute movie. Since it was a Ron Howard movie, we had to play "spot the brother" - a game we play whenever we see a Ron Howard movie...always looking for Ron's brother, Clint Howard to appear in the movie (he does about 10 minutes in, during a bar scene).
At the time, Darryl Hannah was relatively unknown, but not after this movie - it made her a superstar !
Anyway.....during a scene in the movie, when the Mermaid is on land, Tom's character, Allen, asks her for her name. She tells him it is hard to say in English and she says it and breaks all the TVs in the showroom (you can see a bit of it in the trailer below).
He tells her they need an easier name, they are on Madison Avenue, she looks at the sign and says "Madison". He replies "Madison?? That's not a name! And .... he was right, it wasn't a name. Not a first name anyway.
Facts about the name Madison:
In 1984, the year Splash was released, the name Madison did not chart as a girl's name.
In 1985, nearly 300 girls were given the name, and it entered the top 1000 chart at 628.
In 1986, 644 girls were given the name, and it jumped to 366.
And so on, and so on...In 2001, it was the #2 name for a girl.
Just look at this chart of the number of girls named Madison - see, it doesn't even start until after Splash was released ( source )