Life Master Jack Young says it is "fishing for cheap tactics against fish"
Fishing Pole Trap

The Fishing Pole concept is as old as Greco, you can find examples in the first 20 games in Megadatabase. LM roommate Jack Young calls it the Fishing Pole - the idea is to use cheap tactics against fish. Knight is the bait, rookpawn is the Fishing rod, weak player =fish grabbing the bait. I have played over 10,000 Fishing Poles. much analysis and games in BrianWallChess@Yahoogroups.com, www.Chesslike an Animal, any book by Joel Johnson and many Youtube videos.

Life Master Jack Young invented the term Fishing Pole. The idea is as old as Greco. He told me, I am fishing for cheap tactics against fish. The Knight on g4 is the bait, the pawn on h5 the Fishing Rod and the fish is a weak player who bites the bait.

Anyone know why it's called the Fishing Pole?
I don't know if this is true or not, but someone here on the boards said they thought it was named that because Fischer invented it.
Certainly not true. Anderssen's famous miniature against Carl Mayet features it (see http://chessskill.blogspot.com/2014/12/training-with-anderssen.html).
This game BTW is so famous that no one knows whether it was played in London or Berlin, whether the date was 1851 or 1859.

I´ve used this trap in some blitz games from time to time. Of course it´s dubious, but nevertheless it was good enough for a 1600 player to beat Walter Browne. Ok, it was a simul, but he sure opened the gates of hell..
Take a look at Walter here: https://www.youtube.com/watch?v=pnN9mqed3l0

Old post and didn't read all the responses. That being said;
I would think that ....Ng4 would be like sticking your bait in the water to see if your opponent would strike. Hence the fishing reference.
My 2 cents,
M

I bet this opening is similar to what greco made on his opening.....if somebody here knows the "giuoco piano trap"...it is a quite similar to this trap
The Greco Gambit in the Italian opening does not involve a fishing pole.
Example of Greco Gambit from Greco's games.
Example of fishing pole from a game played or not played in London or Berlin in 1851 or 1859.
I've never used it simply because if you're opponent is not enough of a beginner to fall for silly tricks it's of questionable use, and you constantly have to worry about the position changing and it becoming safe to take.