Random insults?

[What Comes After]

I was always wondering where people come up with these random insults, and I was also wondering if any of you guys got insulted and didnt even know what the hell it means.

A friend of mine, with whom I have a love-hate friendship with, called me a fiddlestick in a fit of rage, then she stormed off.

So.... what the hell is a fiddlestick?
I looked it up, pretty sure Im not part of a violin....
So help me out here, the hell does it mean?
Also state your encounters with unknown insults o ~o  

[Esiris]

It means nonsense. Your friend probably didn't use the word correctly.  

[What Comes After]

Wait.
It means nonsense or it is nonsense?  

[chaoskaye]

I got this definition off urban dictionary. Link.

"Like the other definitions, a mild sweary word, but used as a get-out when you start to say '********' somewhere you can't."

Maybe she was using it in that sense.