Scripting Define symbol for Development builds?

Is there a scripting define symbol that you can use so that some debug code is only compiled on dev builds? I want to use it in unison with the UNITY_EDITOR define

Conditional attributes is probably what you are after:

#define MY_DEBUG_SYMBOL

[System.Diagnostics.Conditional("MY_DEBUG_SYMBOL")] 
public void MyFunction()
{
    // Your code
}    

void SomeOtherFunction()
{
    MyFunction();
}

If MY_DEBUG_SYMBOL is defined, MyFunction won’t get called.

Documentation: here

And a detailed discussion here

The symbol is DEVELOPMENT_BUILD:

You can also use the DEVELOPMENT_BUILD define to identify whether your script is running in a player which was built with the “Development Build” option enabled.